190 research outputs found

    Secretion of MCP-1 and other paracrine factors in a novel tumor-bone coculture model

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    BackgroundThe bone-tumor microenvironment encompasses unique interactions between the normal cells of the bone and marrow cavity and the malignant cells from a primary or metastasized cancer. A multitude of paracrine factors within this microenvironment such as the growth factor, TGF-beta, and the chemokine, MCP-1, are secreted by many of these cell types. These factors can act in concert to modulate normal and malignant cell proliferation, malignant cell migration and invasion and, often, mediate bone cancer pain. Although many valuable in vitro and in vivo models exist, identifying the relevant paracrine factors and deciphering their interactions is still a challenge. The aim of our study is to test an ex vivo coculture model that will allow monitoring of the expression, release and regulation of paracrine factors during interactions of an intact femur explant and tumor cells.MethodsIntact or marrow-depleted neonatal mouse femurs and select murine and human sarcoma or carcinoma cell lines were incubated singly or in coculture in specialized well plates. Viability of the bone and cells was determined by immunohistochemical stains, microscopy and marrow cytopreps. Secretion and mRNA expression of paracrine factors was quantitated by ELISA and real-time RT-PCR.ResultsCompartments of the bone were optimally viable for up to 48 h in culture and tumor cells for up to 4 days. Bone was the major contributor of TGF-beta and MMP2 whereas both bone and sarcoma cells secreted the chemokine MCP-1 in cocultures. Synergistic interaction between the femur and sarcoma resulted in enhanced MCP-1 secretion and expression in cocultures and was dependent on the presence of the hematopoietic component of the bone as well as other bone cells. In contrast, coculturing with breast carcinoma cells resulted in reduction of TGF-beta and MCP-1 secretion from the bone.ConclusionThese studies illustrate the feasibility of this model to examine paracrine interactions between intact bone and tumor cells. Further study of unique regulation of MCP-1 secretion and signaling between these cell types in different types of cancer will be possible using this simulated microenvironment

    Updated measurements of exclusive J/ψ and ψ(2S) production cross-sections in pp collisions at √s = 7 TeV

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    The differential cross-section as a function of rapidity has been measured for the exclusive production of J/ψ and ψ(2S) mesons in proton–proton collisions at √s = 7 TeV, using data collected by the LHCb experiment, corresponding to an integrated luminosity of 930 pb−1. The cross-sections times branching fractions to two muons having pseudorapidities between 2.0 and 4.5 are measured to be where the first uncertainty is statistical and the second is systematic. The measurements agree with next-to-leading order QCD predictions as well as with models that include saturation effects

    Observation of Two New Excited Ξb0 States Decaying to Λb0 K-π+

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    Two narrow resonant states are observed in the Λb0K-π+ mass spectrum using a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the LHCb experiment and corresponding to an integrated luminosity of 6 fb-1. The minimal quark content of the Λb0K-π+ system indicates that these are excited Ξb0 baryons. The masses of the Ξb(6327)0 and Ξb(6333)0 states are m[Ξb(6327)0]=6327.28-0.21+0.23±0.12±0.24 and m[Ξb(6333)0]=6332.69-0.18+0.17±0.03±0.22 MeV, respectively, with a mass splitting of Δm=5.41-0.27+0.26±0.12 MeV, where the uncertainties are statistical, systematic, and due to the Λb0 mass measurement. The measured natural widths of these states are consistent with zero, with upper limits of Γ[Ξb(6327)0]<2.20(2.56) and Γ[Ξb(6333)0]<1.60(1.92) MeV at a 90% (95%) credibility level. The significance of the two-peak hypothesis is larger than nine (five) Gaussian standard deviations compared to the no-peak (one-peak) hypothesis. The masses, widths, and resonant structure of the new states are in good agreement with the expectations for a doublet of 1D Ξb0 resonances

    Canagliflozin and Renal Outcomes in Type 2 Diabetes and Nephropathy

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    BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to 300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m 2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years

    Studies of beauty baryon decays to D0ph− and Λ+ch− final states

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    Decays of beauty baryons to the D0ph− and Λ+ch− final states (where h indicates a pion or a kaon) are studied using a data sample of pp collisions, corresponding to an integrated luminosity of 1.0  fb−1, collected by the LHCb detector. The Cabibbo-suppressed decays Λ0b→D0pK− and Λ0b→Λ+cK− are observed, and their branching fractions are measured with respect to the decays Λ0b→D0pπ− and Λ0b→Λ+cπ−. In addition, the first observation is reported of the decay of the neutral beauty-strange baryon Ξ0b to the D0pK− final state, and a measurement of the Ξ0b mass is performed. Evidence of the Ξ0b→Λ+cK− decay is also reported

    Measurement of the CKM angle Îł\gamma using B0→DK∗0B^0 \rightarrow D K^{*0} with D→KS0π+π−D \rightarrow K^0_S \pi^+ \pi^- decays

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    A model-dependent amplitude analysis of the decay B0→D(KS0π+π−)K∗0B^0\rightarrow D(K^0_S\pi^+\pi^-) K^{*0} is performed using proton-proton collision data corresponding to an integrated luminosity of 3.0fb−1^{-1}, recorded at s=7\sqrt{s}=7 and 8TeV8 TeV by the LHCb experiment. The CP violation observables x±x_{\pm} and y±y_{\pm}, sensitive to the CKM angle Îł\gamma, are measured to be \begin{eqnarray*} x_- &=& -0.15 \pm 0.14 \pm 0.03 \pm 0.01, y_- &=& 0.25 \pm 0.15 \pm 0.06 \pm 0.01, x_+ &=& 0.05 \pm 0.24 \pm 0.04 \pm 0.01, y_+ &=& -0.65^{+0.24}_{-0.23} \pm 0.08 \pm 0.01, \end{eqnarray*} where the first uncertainties are statistical, the second systematic and the third arise from the uncertainty on the D→KS0π+π−D\rightarrow K^0_S \pi^+\pi^- amplitude model. These are the most precise measurements of these observables. They correspond to Îł=(80−22+21)∘\gamma=(80^{+21}_{-22})^{\circ} and rB0=0.39±0.13r_{B^0}=0.39\pm0.13, where rB0r_{B^0} is the magnitude of the ratio of the suppressed and favoured B0→DK+π−B^0\rightarrow D K^+ \pi^- decay amplitudes, in a KπK\pi mass region of ±50MeV\pm50 MeV around the K∗(892)0K^*(892)^0 mass and for an absolute value of the cosine of the K∗0K^{*0} decay angle larger than 0.40.4.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-007.htm
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