299 research outputs found
Benefits and risks of the hormetic effects of dietary isothiocyanates on cancer prevention
The isothiocyanate (ITC) sulforaphane (SFN) was shown at low levels (1-5 µM) to promote cell proliferation to 120-143% of the controls in a number of human cell lines, whilst at high levels (10-40 µM) it inhibited such cell proliferation. Similar dose responses were observed for cell migration, i.e. SFN at 2.5 µM increased cell migration in bladder cancer T24 cells to 128% whilst high levels inhibited cell migration. This hormetic action was also found in an angiogenesis assay where SFN at 2.5 µM promoted endothelial tube formation (118% of the control), whereas at 10-20 µM it caused significant inhibition. The precise mechanism by which SFN influences promotion of cell growth and migration is not known, but probably involves activation of autophagy since an autophagy inhibitor, 3-methyladenine, abolished the effect of SFN on cell migration. Moreover, low doses of SFN offered a protective effect against free-radical mediated cell death, an effect that was enhanced by co-treatment with selenium. These results suggest that SFN may either prevent or promote tumour cell growth depending on the dose and the nature of the target cells. In normal cells, the promotion of cell growth may be of benefit, but in transformed or cancer cells it may be an undesirable risk factor. In summary, ITCs have a biphasic effect on cell growth and migration. The benefits and risks of ITCs are not only determined by the doses, but are affected by interactions with Se and the measured endpoint
Recommended from our members
Multiparticle azimuthal correlations for extracting event-by-event elliptic and triangular flow in Au + Au collisions at sNN =200 GeV
We present measurements of elliptic and triangular azimuthal anisotropy of charged particles detected at forward rapidity 1<|η|<3 in Au + Au collisions at sNN=200 GeV, as a function of centrality. The multiparticle cumulant technique is used to obtain the elliptic flow coefficients v2{2},v2{4},v2{6}, and v2{8}, and triangular flow coefficients v3{2} and v3{4}. Using the small-variance limit, we estimate the mean and variance of the event-by-event v2 distribution from v2{2} and v2{4}. In a complementary analysis, we also use a folding procedure to study the distributions of v2 and v3 directly, extracting both the mean and variance. Implications for initial geometrical fluctuations and their translation into the final-state momentum distributions are discussed
Demographic and behavioral characteristics of non-sex worker females attending sexually transmitted disease clinics in Japan: a nationwide case-control study
<p>Abstract</p> <p>Background</p> <p>Although number of sexually transmitted infections (STIs) reported in STI surveillance increased rapidly for women in Japan during the 1990s, the sexual behavior of women potentially at risk of STI infection remains unknown.</p> <p>Methods</p> <p>In order to determine the demographic and behavioral characteristics of non-sex worker (SW) females attending STI clinics, female attendees (n = 145), excluding SW, from nine clinics across Japan and female controls from the general population (n = 956), both aged 18-50 years, were compared using two data sets of nationwide sexual behavior surveys conducted in 1999.</p> <p>Results</p> <p>Although the occupation-type and education level were unrelated to STI clinic attendance in multivariate analysis, non-SW females attending STI clinics were younger (adjusted odds ratios [AOR] = 0.94, 95%CI: 0.89, 0.99), and more likely to be unmarried (AOR = 4.11, 95% CI: 1.73, 9.77) than the controls from the general population. In the previous year, STI clinic attendees were more likely to have had multiple partnerships (AOR = 3.09, 95% CI: 1.42, 6.71) and unprotected vaginal sex with regular partners (AOR = 3.59, 95% CI: 1.49, 8.64), and tended to have had their first sexual intercourse at a younger age (AOR = 1.77, 95%CI: 0.89, 3.54) and more unprotected vaginal and/or oral sex with casual partners (AOR = 2.08, 95%CI: 0.75, 5.71). Identical sexual behavior patterns were observed between the female attendees with a current diagnosis of STI (n = 72) and those before diagnosis (n = 73) and between those with a past history of STI (n = 66) and those without (n = 79).</p> <p>Conclusion</p> <p>These results indicate that not only multiple partnerships or unprotected sex with casual partners, but also unprotected vaginal sex within a regular partnership is prevalent among non-SW female STI clinic attendees. The identical sexual behavior patterns observed between female attendees with a current STI diagnosis and those without, and between those attendees with a past history of STI diagnosis and those without, indicate that the result are unlikely confounded with the cases of non-STI infection. This sexual behavior pattern may be predictive of STI infection among young Japanese women and could have contributed to the STI epidemic in women in Japan during the 1990s.</p
Recommended from our members
Nonperturbative transverse-momentum-dependent effects in dihadron and direct photon-hadron angular correlations in p+p collisions at s =200 GeV
Dihadron and isolated direct photon-hadron angular correlations are measured in p+p collisions at s=200 GeV. The correlations are sensitive to nonperturbative initial-state and final-state transverse momenta kT and jT in the azimuthal nearly back-to-back region Δφ∼π. To have sensitivity to small transverse momentum scales, nonperturbative momentum widths of pout, the out-of-plane transverse-momentum component perpendicular to the trigger particle, are measured. In this region, the evolution of pout can be studied when several different hard scales are measured. These widths are used to investigate possible effects from transverse-momentum-dependent factorization breaking. When accounting for the longitudinal-momentum fraction of the away-side hadron with respect to the near-side trigger particle, the widths are found to increase with the hard scale; this is qualitatively similar to the observed behavior in Drell-Yan and semi-inclusive deep-inelastic scattering interactions, where factorization is predicted to hold. The momentum widths are also studied as a function of center-of-mass energy by comparing to previous measurements at s=510 GeV. The nonperturbative jet widths also appear to increase with s at a similar xT, which is qualitatively consistent to similar measurements in Drell-Yan interactions. Future detailed global comparisons between measurements of processes where transverse-momentum-dependent factorization is predicted to hold and be broken will provide further insight into the role of color in hadronic interactions
Recommended from our members
Nonperturbative-transverse-momentum broadening in dihadron angular correlations in sNN =200 GeV proton-nucleus collisions
The PHENIX collaboration has measured high-pT dihadron correlations in p+p, p+Al, and p+Au collisions at sNN=200 GeV. The correlations arise from inter- and intrajet correlations and thus have sensitivity to nonperturbative effects in both the initial and final states. The distributions of pout, the transverse-momentum component of the associated hadron perpendicular to the trigger hadron, are sensitive to initial- and final-state transverse momenta. These distributions are measured multidifferentially as a function of xE, the longitudinal momentum fraction of the associated hadron with respect to the trigger hadron. The near-side pout widths, sensitive to fragmentation transverse momentum, show no significant broadening between p+Au, p+Al, and p+p. The away-side nonperturbative pout widths are found to be broadened in p+Au when compared to p+p; however, there is no significant broadening in p+Al compared to p+p collisions. The data also suggest that the away-side pout broadening is a function of Ncoll, the number of binary nucleon-nucleon collisions, in the interaction. The potential implications of these results with regard to initial- and final-state transverse-momentum broadening and energy loss of partons in a nucleus, among other nuclear effects, are discussed
Recommended from our members
Measurements of μμ pairs from open heavy flavor and Drell-Yan in p+p collisions at s =200 GeV
PHENIX reports differential cross sections of μμ pairs from semileptonic heavy-flavor decays and the Drell-Yan production mechanism measured in p+p collisions at s=200 GeV at forward and backward rapidity (1.2<|η|<2.2). The μμ pairs from cc, bb, and Drell-Yan are separated using a template fit to unlike- and like-sign muon pair spectra in mass and pT. The azimuthal opening angle correlation between the muons from cc and bb decays and the pair-pT distributions are compared to distributions generated using pythia and powheg models, which both include next-to-leading order processes. The measured distributions for pairs from cc are consistent with pythia calculations. The cc data present narrower azimuthal correlations and softer pT distributions compared to distributions generated from powheg. The bb data are well described by both models. The extrapolated total cross section for bottom production is 3.75±0.24(stat)±0.500.35(syst)±0.45(global) [μb], which is consistent with previous measurements at the Relativistic Heavy Ion Collider in the same system at the same collision energy and is approximately a factor of 2 higher than the central value calculated with theoretical models. The measured Drell-Yan cross section is in good agreement with next-to-leading-order quantum-chromodynamics calculations
Recommended from our members
Measurement of charm and bottom production from semileptonic hadron decays in p+p collisions at s =200 GeV
Measurements of the differential production of electrons from open-heavy-flavor hadrons with charm- and bottom-quark content in p+p collisions at s=200 GeV are presented. The measurements proceed through displaced-vertex analyses of electron tracks from the semileptonic decay of charm and bottom hadrons using the PHENIX silicon-vertex detector. The relative contribution of electrons from bottom decays to inclusive heavy-flavor-electron production is found to be consistent with fixed-order-plus-next-to-leading-log perturbative-QCD calculations within experimental and theoretical uncertainties. These new measurements in p+p collisions provide a precision baseline for comparable forthcoming measurements in A+A collisions
High incidence of silent venous thromboembolism before treatment in ovarian cancer
Venous thromboembolism (VTE) such as deep-vein thrombosis (DVT) and pulmonary thromboembolism (PTE) often occurs after surgery and rarely occurs even before surgery in patients with ovarian cancer. It is well known that levels of plasma D-dimer (DD) before treatment in most ovarian cancer patients are increased. This study therefore examined whether increased levels of DD are associated with presence of VTE before treatment of ovarian cancer. Between November 2004 and March 2007, DD levels prior to initial treatment were measured in 72 consecutive patients with presumed epithelial ovarian cancer (final diagnosis: epithelial ovarian cancer, n=60; and epithelial ovarian borderline malignancy, n=12). Venous ultrasound imaging (VUI) of the lower extremity was conducted for all patients except for two patients in whom DVT was detected by pelvic computed tomography (CT). When DVT was found, pulmonary scintigraphy was subsequently performed to ascertain presence of PTE. D-dimer levels were above the cut-off value (0.5 μg ml−1) in 65 of 72 patients (90.2%). Venous ultrasound imaging or CT revealed DVT in 18 of 72 patients (25.0%) and pulmonary scintigraphy found PTE in 8 patients (11.1%). All patients with VTE were asymptomatic when VTE was found. D-dimer levels were associated with incidence of VTE (0–1.4 μg ml−1; 0 of 26 (0%), 1.5–7.4 μg ml−1; 9 of 30 (30%) and ⩾7.5 μg ml−1; 9 of 16 (56.3%), P for trend=0.0003). However, even if 1.5 μg ml−1 was used as a cut-off value, this had low specificity and positive predictive value (47.2, 38.3%), though it had high sensitivity and negative predictive value (100, 100%). Therefore, ovarian cancer patients with DD level ⩾1.5 μg ml−1 should be examined using VUI to detect silent DVT. Patients with VTE underwent preventive managements including anticoagulant therapy before initial treatment, chemotherapy or surgery, and after surgery. There was no clinical onset of postoperative VTE in all 72 patients. Measurement of DD levels and subsequent ultrasonography revealed that silent or subclinical VTE frequently occurs before surgery in ovarian cancer. The usefulness of preoperative assessment of VTE needs further confirmation in randomised controlled trials
Measurement of high-p_T Single Electrons from Heavy-Flavor Decays in p+p Collisions at sqrt(s) = 200 GeV
The momentum distribution of electrons from decays of heavy flavor (charm and
beauty) for midrapidity |y| < 0.35 in p+p collisions at sqrt(s) = 200 GeV has
been measured by the PHENIX experiment at the Relativistic Heavy Ion Collider
(RHIC) over the transverse momentum range 0.3 < p_T < 9 GeV/c. Two independent
methods have been used to determine the heavy flavor yields, and the results
are in good agreement with each other. A fixed-order-plus-next-to-leading-log
pQCD calculation agrees with the data within the theoretical and experimental
uncertainties, with the data/theory ratio of 1.72 +/- 0.02^stat +/- 0.19^sys
for 0.3 < p_T < 9 GeV/c. The total charm production cross section at this
energy has also been deduced to be sigma_(c c^bar) = 567 +/- 57^stat +/-
224^sys micro barns.Comment: 375 authors from 57 institutions, 6 pages, 3 figures. Submitted to
Physical Review Letters. Plain text data tables for the points plotted in
figures for this and previous PHENIX publications are (or will be) publicly
available at http://www.phenix.bnl.gov/papers.htm
- …