Vitamin A: evidence for its preventive role in human cancer.

Both the provitamin beta-carotene and natural vitamin A and its derivatives (the retinoids) are being proposed as potential chemopreventive agents. The biochemistry and pharmacology of vitamin A suggest a number of mechanisms whereby carcinogenesis can be affected. Epidemiologic studies have consistently demonstrated an increased relative risk of cancer for people with low vitamin A intake or low-to-normal serum retinol values. Chemoprevention trials in humans are only now beginning. In the interim, daily consumption of vitamin-A-containing foods may be a "prescription" worth following

Content Versus Structure in Information Environments: A Longitudinal Analysis of Website Preferences

From the prospective traveler surfing the web for cheap vacations to executives analyzing market trends with a data warehouse, at home and at work, people are confronted with increasingly richer information environments. This study is an attempt at modeling the behavior over time of the “information consumer” (web surfer or executive) in such environments. The objective is to gain a better understanding of how to design the technologies that support and enhance the interaction with these information environments. Two key design variables for information environments are examined: content quality and structural quality. Drawing on research in human-computer interaction and ecological psychology, a behavioral model is developed in which it is postulated that the importance of structural quality will diminish with time, whereas content quality will increaseinimportance. Atwo-stagemethodologyisemployedwhichcombinesalongitudinalexperimentwith a cross-sectional survey. Both the survey and experiment are conducted in the context of informational websites. The experiment provided 178 undergraduates with repeated exposure over several weeks to eight custom-built websites, manipulated to vary in content quality and structural quality for which their preferences (and associated rationales) were elicited at three time points over the course of the experiment. Additionally, 163 of the undergraduates also completed a survey providing data about the effect of content and structure on usage behavior for sites for which they had mature experience. Preliminary results of the experimental data support the hypotheses. The research has potentially significant implications for the design of information environments

Enhancement of regression of cervical intraepithelial neoplasia II (moderate dysplasia) with topically applied all-trans-retinoic acid: a randomized trial.

BackgroundRetinoids enhance differentiation of most epithelial tissues. Epidemiologic studies have shown an inverse relationship between dietary intake or serum levels of vitamin A and the development of cervical dysplasia and/or cervical cancer. Pilot and phase I investigations demonstrated the feasibility of the local delivery of all-trans-retinoic acid (RA) to the cervix using a collagen sponge insert and cervical cap. A phase II trial produced a clinical complete response rate of 50%.PurposeThis randomized phase III trial was designed to determine whether topically applied RA reversed moderate cervical intraepithelial neoplasia (CIN) II or severe CIN.MethodsAnalyses were based on 301 women with CIN (moderate dysplasia, 151 women; severe dysplasia, 150 women), evaluated by serial colposcopy, Papanicolaou cytology, and cervical biopsy. Cervical caps with sponges containing either 1.0 mL of 0.372% beta-trans-RA or a placebo were inserted daily for 4 days when women entered the trial, and for 2 days at months 3 and 6. Patients receiving treatment and those receiving placebo were similar with respect to age, ethnicity, birth-control methods, histologic features of the endocervical biopsy specimen and koilocytotic atypia, and percentage of involvement of the cervix at study. Treatment effects were compared using Fisher's exact test and logistic regression methods. Side effects were recorded, and differences were compared using Fisher's exact test.ResultsRA increased the complete histologic regression rate of CIN II from 27% in the placebo group to 43% in the retinoic acid treatment group (P = .041). No treatment difference between the two arms was evident in the severe dysplasia group. More vaginal and vulvar side effects were seen in the patients receiving RA, but these effects were mild and reversible.ConclusionsA short course of locally applied RA can reverse CIN II, but not more advanced dysplasia, with acceptable local side effects.ImplicationsA derivative of vitamin A can reverse or suppress an epithelial preneoplasia, lending further support to the notion that chemoprevention of human cancer is feasible

Non-commutative field theory approach to two-dimensional vortex liquid system

We investigate the non-commutative (NC) field theory approach to the vortex liquid system restricted to the lowest Landau level (LLL) approximation. NC field theory effectively takes care of the phase space reduction of the LLL physics in a $\star$-product form and introduces a new gauge invariant form of a quartic potential of the order parameter in the Ginzburg-Landau (GL) free energy. This new quartic interaction coupling term has a non-trivial equivalence relation with that obtained by Br\'ezin, Nelson and Thiaville in the usual GL framework. The consequence of the equivalence is discussed.Comment: Add vortex lattice formation, more references, and one autho

15,16-Dihydrotanshinone I, a Compound of Salvia miltiorrhiza Bunge, Induces Apoptosis through Inducing Endoplasmic Reticular Stress in Human Prostate Carcinoma Cells

5,16-dihydrotanshinone I (DHTS) is extracted from Salvia miltiorrhiza Bunge (tanshen root) and was found to be the most effective compound of tanshen extracts against breast cancer cells in our previous studies. However, whether DHTS can induce apoptosis through an endoplasmic reticular (ER) stress pathway was examined herein. In this study, we found that DHTS significantly inhibited the proliferation of human prostate DU145 carcinoma cells and induced apoptosis. DHTS was able to induce ER stress as evidenced by the upregulation of glucose regulation protein 78 (GRP78/Bip) and CAAT/enhancer binding protein homologous protein/growth arrest- and DNA damage-inducible gene 153 (CHOP/GADD153), as well as increases in phosphorylated eukaryotic initiation factor 2α (eIF2α), c-jun N-terminal kinase (JNK), and X-box-binding protein 1 (XBP1) mRNA splicing forms. DHTS treatment also caused significant accumulation of polyubiquitinated proteins and hypoxia-inducible factor (HIF)-1α, indicating that DHTS might be a proteasome inhibitor that is known to induce ER stress or enhance apoptosis caused by the classic ER stress-dependent mechanism. Moreover, DHTS-induced apoptosis was reversed by salubrinal, an ER stress inhibitor. Results suggest that DHTS can induce apoptosis of prostate carcinoma cells via induction of ER stress and/or inhibition of proteasome activity, and may have therapeutic potential for prostate cancer patients

Reduced length of hospital stay in colorectal surgery after implementation of an enhanced recovery protocol.

BACKGROUND: Enhanced recovery after surgery (ERAS) is a multimodal approach to perioperative care that combines a range of interventions to enable early mobilization and feeding after surgery. We investigated the feasibility, clinical effectiveness, and cost savings of an ERAS program at a major U. S. teaching hospital. METHODS: Data were collected from consecutive patients undergoing open or laparoscopic colorectal surgery during 2 time periods, before and after implementation of an ERAS protocol. Data collected included patient demographics, operative, and perioperative surgical and anesthesia data, need for analgesics, complications, inpatient medical costs, and 30-day readmission rates. RESULTS: There were 99 patients in the traditional care group, and 142 in the ERAS group. The median length of stay (LOS) was 5 days in the ERAS group compared with 7 days in the traditional group (P < 0.001). The reduction in LOS was significant for both open procedures (median 6 vs 7 days, P = 0.01), and laparoscopic procedures (4 vs 6 days, P < 0.0001). ERAS patients had fewer urinary tract infections (13% vs 24%, P = 0.03). Readmission rates were lower in ERAS patients (9.8% vs 20.2%, P = 0.02). DISCUSSION: Implementation of an enhanced recovery protocol for colorectal surgery at a tertiary medical center was associated with a significantly reduced LOS and incidence of urinary tract infection. This is consistent with that of other studies in the literature and suggests that enhanced recovery programs could be implemented successfully and should be considered in U.S. hospitals

On the Security of Carrier Phase-based Ranging

Multicarrier phase-based ranging is fast emerging as a cost-optimized solution for a wide variety of proximity-based applications due to its low power requirement, low hardware complexity and compatibility with existing standards such as ZigBee and 6LoWPAN. Given potentially critical nature of the applications in which phase-based ranging can be deployed (e.g., access control, asset tracking), it is important to evaluate its security guarantees. Therefore, in this work, we investigate the security of multicarrier phase-based ranging systems and specifically focus on distance decreasing relay attacks that have proven detrimental to the security of proximity-based access control systems (e.g., vehicular passive keyless entry and start systems). We show that phase-based ranging, as well as its implementations, are vulnerable to a variety of distance reduction attacks. We describe different attack realizations and verify their feasibility by simulations and experiments on a commercial ranging system. Specifically, we successfully reduced the estimated range to less than 3 m even though the devices were more than 50 m apart. We discuss possible countermeasures against such attacks and illustrate their limitations, therefore demonstrating that phase-based ranging cannot be fully secured against distance decreasing attacks

Effects of sulfur-based hemostatic agents and gingival retraction cords handled with latex gloves on the polymerization of polyvinyl siloxane impression materials

OBJECTIVES: This study investigated the possible interactions between three addition silicone materials (Express(®), Aquasil Ultra(®) and Adsil(®)), three hemostatic agents (ferric sulfate, StatGel FS(®); aluminum sulfate, GelCord(®); and aluminum chloride, Hemostop(®)) and gingival retraction cords previously handled with latex gloves to determine whether direct contact with medicaments or indirect contamination by latex in conditions similar to those found in clinical practice inhibit or affect the setting of the impression materials. MATERIAL AND METHODS: A portable device for the simultaneous test of several specimens was specifically developed for this study. Polymerization inhibition was analyzed by examination of the impressions and the molded surface. Ten trials were performed for each addition silicone material used in the study, at a total of 240 study samples. RESULTS: All the samples tested (N=240) were nonreactive regardless of the type of combination used. CONCLUSIONS: Aluminum sulfate, ferric sulfate and aluminum chloride hemostatic solutions did not show any inhibitory potential on the addition silicone samples under study, and there were no changes in polymerization as a result of contact between addition silicone and retraction cords handled with latex gloves