http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Induction of Apoptosis in HeLa Cells via Caspase Activation by Resveratrol and Genistein
Sivanesan Dhandayuthapani,Palanisamy Marimuthu,Vanessa Hormann,James Kumi-Diaka,Appu Rathinavelu 한국식품영양과학회 2013 Journal of medicinal food Vol.16 No.2
Selectively inducing apoptosis in cancer cells is a much desired strategy when tolerance toward side effects is minimal during chemotherapy. In our search for natural products that can induce apoptosis in human cervical cancer cells (HeLa), we selected resveratrol and genistein for our study. We conducted several experiments to test whether genistein can synergistically enhance the apoptotic potential of resveratrol at doses lower than the usual cytotoxic dose. Both resveratrol and genistein were able to induce apoptosis by enhancing the activities of caspase-9 and caspase-3 by themselves and also in combination. After 24 h of exposure to resveratrol and genistein, individually or in combination, lowered mitochondrial membrane potential was observed in HeLa cells. In addition, the mitochondrial membrane potential in HeLa cells was decreased, forcing JC-1 to stay in the monomeric form. The monomeric JC-1(5,5′,6,6′ -tetrachloro-1,1′,3,3′-tetraethyl benzimedazolyl carbocyanine iodide) emitted green fluorescence. In the control group, the color of the fluorescence was red due to aggregation of JC-1 in the physiological pH. The treatment groups exhibited DNA fragmentation as the hallmark of apoptotic nuclear features. We also detected an obvious decrease in the level of HDM2 gene expression after both individual and combination treatments with resveratrol and genistein. Our findings suggest that resveratrol and genistein when combined can induce apoptosis at doses lower than usual doses, through the activation of caspases cascade, and by decreasing the expression of HDM2.
Genistein-Selenium Combination Induces Growth Arrest in Prostate Cancer Cells
James Kumi-Diaka,Kendra Merchant,Alberto Haces,Vanessa Hormann,Michelle Johnson 한국식품영양과학회 2010 Journal of medicinal food Vol.13 No.4
The prognosis for patients with metastasized prostate cancer is still poor, despite conventional aggressive therapeutic modalities. Several in vitro studies together with animal models and epidemiological studies have indicated that phytochemicals can be antitumorigenic and may be protective against human cancers. However, the potential antitumor effects of genistein isoflavone, a widely studied nutrient phytochemical, have been equivocal. In this study, we investigated the effects of genistein-selenium (Gn-Se) combination on chemosensitivity and matrix metalloproteinase-2 (MMP-2) expression levels in PC3 (hormone-independent) and LNCaP (hormone-dependent) prostate cancer cells. 3-(4,5-Dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium staining and ATP bioassay showed that genistein, selenium, and Gn-Se combination significantly inhibited growth of LNCaP and PC3 cells in a dose- and time-dependent manner, independent of hormonal status, and with no significant differences in chemosensitivity between LNCaP and PC3. Gn-Se combination induced significantly the greatest growth inhibition in both cell lines. Growth inhibition was through apoptosis induction. The treatment-induced apoptotic cascades are caspase-dependent, with evidence of an alternative non-caspase pathway(s). Treatment also induced a dose- and time-dependent decrease in MMP-2 expression levels in PC3 and LNCaP with no significant differences between the two cells. Gn-Se combination induced the greatest depression in MMP-2. Overall, none of the treatment modalities had any significant inhibitory effect in normal prostate epithelial cells. The data obtained from the present study indicate that Gn-Se combination may have chemopreventive value and/or may be adjuvant to standard therapy for prostate tumors independent of hormonal status. MMP-2 expression in cancer cells has been associated with active invasion and metastasis.
Search for heavy narrow dilepton resonances in pp collisions at s=7 TeV and s=8 TeV
CMS Collaboration,Chatrchyan, S.,Khachatryan, V.,Sirunyan, A.M.,Tumasyan, A.,Adam, W.,Aguilo, E.,Bergauer, T.,Dragicevic, M.,Ero, J.,Fabjan, C.,Friedl, M.,Fruhwirth, R.,Ghete, V.M.,Hormann, N.,Hrubec, North-Holland Pub. Co 2013 Physics letters: B Vol.720 No.1
An updated search for heavy narrow resonances decaying to muon or electron pairs using the CMS detector is presented. Data samples from pp collisions at s=7 TeV and 8 TeV at the LHC, with integrated luminosities of up to 5.3 and 4.1 fb<SUP>-1</SUP>, respectively, are combined. No evidence for a heavy narrow resonance is observed. The analysis of the combined data sets excludes, at 95% confidence level, a Sequential Standard Model Z<SUB>SSM</SUB><SUP>'</SUP> resonance lighter than 2590 GeV, a superstring-inspired Z<SUB>ψ</SUB><SUP>'</SUP> lighter than 2260 GeV, and Kaluza-Klein gravitons lighter than 2390 (2030) GeV, assuming that the coupling parameter k/M@?<SUB>Pl</SUB> is 0.10 (0.05). These are the most stringent limits to date.
Observation of long-range, near-side angular correlations in pPb collisions at the LHC
CMS Collaboration,Chatrchyan, S.,Khachatryan, V.,Sirunyan, A.M.,Tumasyan, A.,Adam, W.,Aguilo, E.,Bergauer, T.,Dragicevic, M.,Ero, J.,Fabjan, C.,Friedl, M.,Fruhwirth, R.,Ghete, V.M.,Hormann, N.,Hrubec, North-Holland Pub. Co 2013 Physics letters: B Vol.718 No.3
Results on two-particle angular correlations for charged particles emitted in pPb collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV are presented. The analysis uses two million collisions collected with the CMS detector at the LHC. The correlations are studied over a broad range of pseudorapidity, η, and full azimuth, φ, as a function of charged particle multiplicity and particle transverse momentum, p<SUB>T</SUB>. In high-multiplicity events, a long-range (2<|Δη|<4), near-side (Δφ~0) structure emerges in the two-particle Δη-Δφ correlation functions. This is the first observation of such correlations in proton-nucleus collisions, resembling the ridge-like correlations seen in high-multiplicity pp collisions at s=7 TeV and in AA collisions over a broad range of center-of-mass energies. The correlation strength exhibits a pronounced maximum in the range of p<SUB>T</SUB>=1-1.5 GeV/c and an approximately linear increase with charged particle multiplicity for high-multiplicity events. These observations are qualitatively similar to those in pp collisions when selecting the same observed particle multiplicity, while the overall strength of the correlations is significantly larger in pPb collisions.
CMS Collaboration,Chatrchyan, S.,Khachatryan, V.,Sirunyan, A.M.,Tumasyan, A.,Adam, W.,Bergauer, T.,Dragicevic, M.,Ero, J.,Fabjan, C.,Friedl, M.,Fruhwirth, R.,Ghete, V.M.,Hammer, J.,Hormann, N.,Hrubec, North-Holland Pub. Co 2012 Physics letters: B Vol.714 No.2
The Λ<SUB>b</SUB> differential production cross section and the cross section ratio σ(Λ@?<SUB>b</SUB>)/σ(Λ<SUB>b</SUB>) are measured as functions of transverse momentum p<SUB>T</SUB><SUP>Λ'b</SUP> and rapidity |y<SUP>Λ'b</SUP>| in pp collisions at s=7 TeV using data collected by the CMS experiment at the LHC. The measurements are based on Λ<SUB>b</SUB> decays reconstructed in the exclusive final state J/ψΛ, with the subsequent decays J/ψ→μ<SUP>+</SUP>μ<SUP>-</SUP> and Λ→pπ, using a data sample corresponding to an integrated luminosity of 1.9 fb<SUP>-1</SUP>. The product σ(Λ<SUB>b</SUB>)xB(Λ<SUB>b</SUB>→J/ψΛ) versus p<SUB>T</SUB><SUP>Λ'b</SUP> falls faster than that of b mesons. The measured value of σ(Λ<SUB>b</SUB>)xB(Λ<SUB>b</SUB>→J/ψΛ) for p<SUB>T</SUB><SUP>Λ'b</SUP>>10 GeV and |y<SUP>Λ'b</SUP>|<2.0 is 1.16+/-0.06+/-0.12 nb, and the integrated σ(Λ@?<SUB>b</SUB>)/σ(Λ<SUB>b</SUB>) ratio is 1.02+/-0.07+/-0.09, where the uncertainties are statistical and systematic, respectively.
Study of W boson production in PbPb and pp collisions at s<sub>NN</sub>=2.76 TeV
CMS Collaboration,Chatrchyan, S.,Khachatryan, V.,Sirunyan, A.M.,Tumasyan, A.,Adam, W.,Bergauer, T.,Dragicevic, M.,Ero, J.,Fabjan, C.,Friedl, M.,Fruhwirth, R.,Ghete, V.M.,Hammer, J.,Hormann, N.,Hrubec, North-Holland Pub. Co 2012 Physics letters: B Vol.715 No.1
A measurement is presented of W-boson production in PbPb collisions carried out at a nucleon-nucleon (NN) centre-of-mass energy s<SUB>NN</SUB> of 2.76 TeV at the LHC using the CMS detector. In data corresponding to an integrated luminosity of 7.3 μb<SUP>-1</SUP>, the number of W→μν<SUB>μ</SUB> decays is extracted in the region of muon pseudorapidity |η<SUP>μ</SUP>|<2.1 and transverse momentum p<SUB>T</SUB><SUP>μ</SUP>>25 GeV/c. Yields of muons found per unit of pseudorapidity correspond to (159+/-10(stat.)+/-12(syst.))x10<SUP>-8</SUP>W<SUP>+</SUP> and (154+/-10(stat.)+/-12(syst.))x10<SUP>-8</SUP>W<SUP>-</SUP> bosons per minimum-bias PbPb collision. The dependence of W production on the centrality of PbPb collisions is consistent with a scaling of the yield by the number of incoherent NN collisions. The yield of W bosons is also studied in a sample of pp interactions at s=2.76 TeV corresponding to an integrated luminosity of 231 nb<SUP>-1</SUP>. The individual W<SUP>+</SUP> and W<SUP>-</SUP> yields in PbPb and pp collisions are found to agree, once the neutron and proton content in Pb nuclei is taken into account. Likewise, the difference observed in the dependence of the positive and negative muon production on pseudorapidity is consistent with next-to-leading-order perturbative QCD calculations.
CMS Collaboration,Chatrchyan, S.,Khachatryan, V.,Sirunyan, A.M.,Tumasyan, A.,Adam, W.,Bergauer, T.,Dragicevic, M.,Ero, J.,Fabjan, C.,Friedl, M.,Fruhwirth, R.,Ghete, V.M.,Hammer, J.,Hormann, N.,Hrubec, North-Holland Pub. Co 2012 Physics letters: B Vol.716 No.2
A search is presented for physics beyond the standard model (BSM) in events with a Z boson, jets, and missing transverse energy (E<SUB>T</SUB><SUP>miss</SUP>). This signature is motivated by BSM physics scenarios, including supersymmetry. The study is performed using a sample of proton-proton collision data collected at s=7 TeV with the CMS experiment at the LHC, corresponding to an integrated luminosity of 4.98 fb<SUP>-1</SUP>. The contributions from the dominant standard model backgrounds are estimated from data using two complementary strategies, the jet-Z balance technique and a method based on modeling E<SUB>T</SUB><SUP>miss</SUP> with data control samples. In the absence of evidence for BSM physics, we set limits on the non-standard-model contributions to event yields in the signal regions and interpret the results in the context of simplified model spectra. Additional information is provided to facilitate tests of other BSM physics models.
Search for narrow resonances in dilepton mass spectra in pp collisions at s=7TeV
CMS Collaboration,Chatrchyan, S.,Khachatryan, V.,Sirunyan, A.M.,Tumasyan, A.,Adam, W.,Bergauer, T.,Dragicevic, M.,Ero, J.,Fabjan, C.,Friedl, M.,Fruhwirth, R.,Ghete, V.M.,Hammer, J.,Hormann, N.,Hrubec, North-Holland Pub. Co 2012 Physics letters: B Vol.714 No.2
A search for narrow, high-mass resonances decaying to electron or muon pairs has been performed using pp collision data collected at s=7TeV by the CMS experiment in 2011. The data sample corresponds to an integrated luminosity of approximately 5 fb<SUP>-1</SUP>. The event yields observed in the signal regions are consistent with predictions of the standard model backgrounds, and upper limits on the cross section times branching fraction for a resonance decaying to dileptons are extracted from a shape analysis of the dilepton invariant mass distribution. The resulting mass limits at 95% confidence level are 2330 GeV for the Z<SUP>'</SUP> in the Sequential Standard Model, 2000 GeV for the superstring-inspired Z<SUB>ψ</SUB><SUP>'</SUP> resonance, 890 (540) GeV for the Stueckelberg extension Z<SUB>St</SUB><SUP>'</SUP> with the mass parameter ε=0.06 (0.04), and 2140 (1810) GeV for Kaluza-Klein gravitons with the coupling parameter k/M@?<SUB>Pl</SUB> of 0.10 (0.05). These limits are the most stringent to date.
Jet momentum dependence of jet quenching in PbPb collisions at s<sub>NN</sub>=2.76 TeV
CMS Collaboration,Chatrchyan, S.,Khachatryan, V.,Sirunyan, A.M.,Tumasyan, A.,Adam, W.,Bergauer, T.,Dragicevic, M.,Ero, J.,Fabjan, C.,Friedl, M.,Fruhwirth, R.,Ghete, V.M.,Hammer, J.,Hormann, N.,Hrubec, North-Holland Pub. Co 2012 Physics letters: B Vol.712 No.3
Dijet production in PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV is studied with the CMS detector at the LHC. A data sample corresponding to an integrated luminosity of 150 μb<SUP>-1</SUP> is analyzed. Jets are reconstructed using combined information from tracking and calorimetry, using the anti-k<SUB>T</SUB> algorithm with R=0.3. The dijet momentum balance and angular correlations are studied as a function of collision centrality and leading jet transverse momentum. For the most peripheral PbPb collisions, good agreement of the dijet momentum balance distributions with pp data and reference calculations at the same collision energy is found, while more central collisions show a strong imbalance of leading and subleading jet transverse momenta attributed to the jet-quenching effect. The dijets in central collisions are found to be more unbalanced than the reference, for leading jet transverse momenta up to the highest values studied.
CMS Collaboration,Chatrchyan, S.,Khachatryan, V.,Sirunyan, A.M.,Tumasyan, A.,Adam, W.,Bergauer, T.,Dragicevic, M.,Ero, J.,Fabjan, C.,Friedl, M.,Fruhwirth, R.,Ghete, V.M.,Hammer, J.,Hormann, N.,Hrubec, North-Holland Pub. Co 2013 Physics letters: B Vol.718 No.3
A search is presented for physics beyond the standard model (BSM) in final states with a pair of opposite-sign isolated leptons accompanied by jets and missing transverse energy. The search uses LHC data recorded at a center-of-mass energy s=7 TeV with the CMS detector, corresponding to an integrated luminosity of approximately 5 fb<SUP>-1</SUP>. Two complementary search strategies are employed. The first probes models with a specific dilepton production mechanism that leads to a characteristic kinematic edge in the dilepton mass distribution. The second strategy probes models of dilepton production with heavy, colored objects that decay to final states including invisible particles, leading to very large hadronic activity and missing transverse energy. No evidence for an event yield in excess of the standard model expectations is found. Upper limits on the BSM contributions to the signal regions are deduced from the results, which are used to exclude a region of the parameter space of the constrained minimal supersymmetric extension of the standard model. Additional information related to detector efficiencies and response is provided to allow testing specific models of BSM physics not considered in this Letter.