22 research outputs found
Influence of the electric field on the latent heat of the ferroelectric phase transition in KDP
The specific heat, heat flux (DTA trace) and dielectric constant of KDP
ferroelectric crystal have been measured simultaneously for various electric
fields with a conduction calorimeter. The specific heat presents a strong
anomaly but these simultaneous measurements allow us to evaluate the latent
heat accurately. Latent heat decreases with field and the value of critical
electric field --that where latent heat disappears-- is estimated to be
(0.44\pm0.03) kV/cm. Incidentally, we have measured simultaneously the
dielectric permittivity which suggests that latent heat is developed as domains
are growing.Comment: 7 pages, 6 figures, ReVTeX, twocolumn format, to appear in J. Phys.
Cond. Matte
Anti proliferative activity of ELACYTâ„¢ (CP-4055) in combination with cloretazine (VNP40101M), idarubicin, gemcitabine, irinotecan and topotecan in human leukemia and lymphoma cells
This study evaluated combination drug partners for CP-4055, the C18:1Δ9,trans unsaturated fatty acid ester of cytarabine in HL-60 and U937 cells. Growth inhibition was assessed by ATP assay and drug interaction by the combination index and three dimensional methods. Synergy was observed in HL-60 cells for simultaneous combinations of CP-4055 with gemcitabine, irinotecan and topotecan, while combinations with cloretazine (VNP40101M) and idarubicin were additive. In U937 cells, synergy was observed with gemcitabine and additivity for the other drugs. In HL-60, the IC50 concentration of CP-4055 could be reduced 10-fold and that of gemcitabine 3-fold in combination versus the agents alone, an interaction that was independent of drug sequence, ratio and exposure time. In contrast, interactions of CP-4055 with the topoisomerase inhibitors became antagonistic when the drugs were administered 24 h prior to CP-4055 and at certain drug ratios, particularly in U937 cells. In summary, CP-4055 produced additive to synergistic anti proliferative activity when combined simultaneously with drugs from four mechanistic classes in cell culture models of human leukemia and lymphoma. The impact of drug sequence and ratio on the interactions argues for incorporation of these parameters into the design of combination chemotherapy regimens
PCR primers and IHC antibodies used to probe respective proteins.
<p>PCR primers and IHC antibodies used to probe respective proteins.</p
SHG microscopy of selected samples identifying fibrillar collagens (white) counter stained with DAPI (blue).
<p> is shown to give weight to the darker end of the detector, as described in Materials and Methods. Scale bars are 20 µm.</p
mRNA expression levels relative to GAPDH of selected genes relevant to chondrogenic differentiation, measured by RT qPCR.
<p>Structural ECM proteins (a–d) and enzymes involved in collagen processing and degradation (e–h).</p
Samples characterized in this study differed in cell seeding density (δ) and calcium concentration ([Ca<sup>2+</sup>]) in the differentiation medium.
<p>All samples were cultured with 1.05 mM calcium until day 10, and then switched to the given concentrations.</p
TEM micrograph (combined from two tiles) of sample 10-B after three weeks of chondrogenic differentiation, showing distinct zones of matrix radially out from the cell surface.
<p>Scale bar is 1 µm.</p