273 research outputs found

    Perceived risk of regular cannabis use in the United States from 2002 to 2012: Differences by sex, age, and race/ethnicity

    Get PDF
    Introduction: Cannabis is one of the most widely used psychoactive substances in the United States (U.S.). Perceived risk of use is associated with substance use; the recent debate surrounding medicalization and legalization of cannabis in the U.S. has the potential to impact perceived risk of use. Recent estimates are needed to assess temporal changes in, and identify correlates of, perceived risk of cannabis use. Methods: Utilizing data from the 2002–2012 survey years of the National Survey on Drug Use and Health, chi-squared statistics and logistic regression were used to describe temporal changes in perceived risk of regular cannabis use (i.e., once or twice a week), to explore correlates of perceived risk, and to report frequency of cannabis use. Results: Between 2002 and 2012, perceived great risk of regular cannabis use varied significantly overall (p < 0.001). The prevalence of past year non-daily (p < 0.001) and daily use varied significantly during this time (p < 0.001). Controlling for survey year and other confounders, characteristics associated with increased odds of perceived great risk of regular cannabis use included: female sex; Non-White race/ethnicity; age 50+; and family income of 20,00049,999.Characteristicsassociatedwithdecreasedoddsofperceivedgreatriskincluded:ages1217and1825;highschooleducationorgreater;totalfamilyincomeof20,000-49,999. Characteristics associated with decreased odds of perceived great risk included: ages 12–17 and 18–25; high school education or greater; total family income of 75,000+; past year non-daily and daily cannabis use; and survey years 2008–2012. Conclusions: Findings characterize trends of perceived risk of regular cannabis use, and past year non-daily and daily cannabis use. Longitudinal studies of the influence of legal status of cannabis at the state-level are needed

    International Legal Aspects of Fight against the International Terrorism: Problems of Legal Regulation

    Get PDF
    The article analyzes the legal problems existing in the regulation of relations that arose as a result of counteracting acts of international  terrorism; the provisions of Russian legislation and legal act of some  foreign states, as well as the principles and norms of international law in the field of combating terrorism are being examined; gaps and  contradictions in legal regulation in the antiterrorist sphere are revealed, which require legislative consolidation and international legal regulation

    Uncertainty of Regulation in the Fight against Extremism in International and National Law

    Get PDF
    The article analyzes the concept of “extremism” in national and international law, examines the problem of criminalization of extremism in the legislation of the Russian Federation, foreign states and international legal acts, identifes lacunas and contradictions in the legal regulation of relations aimed at countering extremism, it is argued that legal certainty is one of the factors of the effectiveness of international cooperation in the fght against extremism and terrorism

    Decreased MCM2-6 in Drosophila S2 cells does not generate significant DNA damage or cause a marked increase in sensitivity to replication interference.

    Get PDF
    A reduction in the level of some MCM proteins in human cancer cells (MCM5 in U20S cells or MCM3 in Hela cells) causes a rapid increase in the level of DNA damage under normal conditions of cell proliferation and a loss of viability when the cells are subjected to replication interference. Here we show that Drosophila S2 cells do not appear to show the same degree of sensitivity to MCM2-6 reduction. Under normal cell growth conditions a reduction of >95% in the levels of MCM3, 5, and 6 causes no significant short term alteration in the parameters of DNA replication or increase in DNA damage. MCM depleted cells challenged with HU do show a decrease in the density of replication forks compared to cells with normal levels of MCM proteins, but this produces no consistent change in the levels of DNA damage observed. In contrast a comparable reduction of MCM7 levels has marked effects on viability, replication parameters and DNA damage in the absence of HU treatment

    Feasibility of an in situ measurement device for bubble size and distribution

    Get PDF
    The feasibility of in situ measurement device for bubble size and distribution was explored. A novel in situ probe measurement system, the EnviroCam™, was developed. Where possible, this probe incorporated strengths, and minimized weaknesses of historical and currently available real-time measurement methods for bubbles. The system was based on a digital, high-speed, high resolution, modular camera system, attached to a stainless steel shroud, compatible with standard Ingold ports on fermenters. Still frames and/or video were produced, capturing bubbles passing through the notch of the shroud. An LED light source was integral with the shroud. Bubbles were analyzed using customized commercially available image analysis software and standard statistical methods. Using this system, bubble sizes were measured as a function of various operating parameters (e.g., agitation rate, aeration rate) and as a function of media properties (e.g., viscosity, antifoam, cottonseed flour, and microbial/animal cell broths) to demonstrate system performance and its limitations. For selected conditions, mean bubble size changes qualitatively compared favorably with published relationships. Current instrument measurement capabilities were limited primarily to clear solutions that did not contain large numbers of overlapping bubbles

    Interaction of the Retinoblastoma Protein with Orc1 and Its Recruitment to Human Origins of DNA Replication

    Get PDF
    Background: The retinoblastoma protein (Rb) is a crucial regulator of cell cycle progression by binding with E2F transcription factor and repressing the expression of a variety of genes required for the G1-S phase transition. Methodology/Principal Findings: Here we show that Rb and E2F1 directly participate in the control of initiation of DNA replication in human HeLa, U2OS and T98G cells by specifically binding to origins of DNA replication in a cell cycle regulated manner. We show that, both in vitro and inside the cells, the largest subunit of the origin recognition complex (Orc1) specifically binds hypo-phosphorylated Rb and that this interaction is competitive with the binding of Rb to E2F1. The displacement of Rb-bound Orc1 by E2F1 at origins of DNA replication marks the progression of the G1 phase of the cell cycle toward the G1-S border. Conclusions/Significance: The participation of Rb and E2F1 in the formation of the multiprotein complex that binds origins of DNA replication in mammalian cells appears to represent an effective mechanism to couple the expression of gene

    Cdc45 Limits Replicon Usage from a Low Density of preRCs in Mammalian Cells

    Get PDF
    Little is known about mammalian preRC stoichiometry, the number of preRCs on chromosomes, and how this relates to replicon size and usage. We show here that, on average, each 100-kb of the mammalian genome contains a preRC composed of approximately one ORC hexamer, 4–5 MCM hexamers, and 2 Cdc6. Relative to these subunits, ∼0.35 total molecules of the pre-Initiation Complex factor Cdc45 are present. Thus, based on ORC availability, somatic cells contain ∼70,000 preRCs of this average total stoichiometry, although subunits may not be juxtaposed with each other. Except for ORC, the chromatin-bound complement of preRC subunits is even lower. Cdc45 is present at very low levels relative to the preRC subunits, but is highly stable, and the same limited number of stable Cdc45 molecules are present from the beginning of S-phase to its completion. Efforts to artificially increase Cdc45 levels through ectopic expression block cell growth. However, microinjection of excess purified Cdc45 into S-phase nuclei activates additional replication foci by three-fold, indicating that Cdc45 functions to activate dormant preRCs and is rate-limiting for somatic replicon usage. Paradoxically, although Cdc45 colocalizes in vivo with some MCM sites and is rate-limiting for DNA replication to occur, neither Cdc45 nor MCMs colocalize with active replication sites. Embryonic metazoan chromatin consists of small replicons that are used efficiently via an excess of preRC subunits. In contrast, somatic mammalian cells contain a low density of preRCs, each containing only a few MCMs that compete for limiting amounts of Cdc45. This provides a molecular explanation why, relative to embryonic replicon dynamics, somatic replicons are, on average, larger and origin efficiency tends to be lower. The stable, continuous, and rate-limiting nature of Cdc45 suggests that Cdc45 contributes to the staggering of replicon usage throughout S-phase, and that replicon activation requires reutilization of existing Cdc45 during S-phase
    corecore