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Supplementary Figure S6 from Caspase-8 Promotes Cell Motility and Calpain Activity under Nonapoptotic Conditions

Caspase-8 is a proapoptotic protease that suppresses neuroblastoma metastasis by inducing programmed cell death. Paradoxically, caspase-8 can also promote cell migration among nonapoptotic cells; here, we show that caspase-8 can promote metastasis when apoptosis is compromised. Migration is enhanced by caspase-8 recruitment to the cellular migration machinery following integrin ligation. Caspase-8 catalytic activity is not required for caspase-8–enhanced cell migration; rather, caspase-8 interacts with a multiprotein complex that can include focal adhesion kinase and calpain 2 (CPN2), enhancing cleavage of focal adhesion substrates and cell migration. Caspase-8 association with CPN2/calpastatin disrupts calpastatin-mediated inhibition of CPN2. In vivo, knockdown of either caspase-8 or CPN2 disrupts metastasis among apoptosis-resistant tumors. This unexpected molecular collaboration provides an explanation for the continued or elevated expression of caspase-8 observed in many tumors. [Cancer Res 2009;69(9):3755–63]

Significant caspase-8 activity has been found in normal and certain tumor cells, suggesting that caspase-8 possesses an alternative, nonapoptotic function that may contribute to tumor progression. In this article, we report that caspase-8 promotes cell motility. In particular, caspase-8 is required for the optimal activation of calpains, Rac, and lamellipodial assembly. This represents a novel nonapoptotic function of caspase-8 acting at the intersection of the caspase-8 and calpain proteolytic pathways to coordinate cell death versus cell motility signaling. (Cancer Res 2006; 66(8): 4273-8)

XLSX file - 146K, Table S1- Data on the genes that differ in expression between primary tumors Th- MYCN, Caspase-8 wild type levels with no BMM, and primary tumors Th-MYCN, deficient caspase-8 with BMM (p

PDF file - 709K, Figure S1. Correlation of relative mean fold changes in expression of genes and microRNAs of the mouse tumor groups by expression- array and by quantitative RT-PCR. Figure S2. Levels of caspase-8 protein in primary tumors and BM secondary tumors. Figure S3. Primary tumors from wild-type or caspase-8 deficient (fl/ko, fl/fl or wt/ko caspase-8) mice had neuroblastoma morphology and stained positive for neuronal markers typical for neuroblastoma. Figure S4. Age at maximum tumor burden of neuroblastoma primary tumors in the Th-MYCN mouse groups. Figure S5. Measuring apoptosis levels by immunostaining for cleaved caspase-3. Figure S6. MYCN expression in the primary Th-MYCN, Th-Cre neuroblastoma tumors. Figure S7. Secondary tumors observed in both the Th-MYCN Caspase-8 wt/wt and the Th-MYCN deficient caspase-8 mouse models.

XLSX file - 77K, Table S3- Data on the microRNAs that differ in expression between primary tumors Th- MYCN, Caspase-8 wild type levels with no BMM, and primary tumors Th-MYCN, deficient caspase-8 with BMM (p

Supplementary Figures 1-5 from Caspase-8 Association with the Focal Adhesion Complex Promotes Tumor Cell Migration and Metastasis

Supplementary Figure Legends S1-S10 from Caspase-8 Promotes Cell Motility and Calpain Activity under Nonapoptotic Conditions

Neuroblastoma, the most common extracranial pediatric solid tumor, is responsible for 15% of all childhood cancer deaths. Patients frequently present at diagnosis with metastatic disease, particularly to the bone marrow. Advances in therapy and understanding of the metastatic process have been limited due, in part, to the lack of animal models harboring bone marrow disease. The widely used transgenic model, the Th-MYCN mouse, exhibits limited metastasis to this site. Here, we establish the first genetic immunocompetent mouse model for metastatic neuroblastoma with enhanced secondary tumors in the bone marrow. This model recapitulates 2 frequent alterations in metastatic neuroblasoma, overexpression of MYCN and loss of caspase-8 expression. Mouse caspase-8 gene was deleted in neural crest lineage cells by crossing a Th-Cre transgenic mouse with a caspase-8 conditional knockout mouse. This mouse was then crossed with the neuroblastoma prone Th-MYCN mouse. Although overexpression of MYCN by itself rarely caused bone marrow metastasis, combining MYCN overexpression and caspase-8 deletion significantly enhanced bone marrow metastasis (37% incidence). Microarray expression studies of the primary tumors mRNAs and microRNAs revealed extracellular matrix structural changes, increased expression of genes involved in epithelial to mesenchymal transition, inflammation, and downregulation of miR-7a and miR-29b. These molecular changes have been shown to be associated with tumor progression and activation of the cytokine TGF-β pathway in various tumor models. Cytokine TGF-β can preferentially promote single cell motility and blood-borne metastasis and therefore activation of this pathway may explain the enhanced bone marrow metastasis observed in this animal model. Cancer Res; 73(13); 4086–97. ©2013 AACR.

XLSX file - 175K, Table S2- Data on the genes that differ in expression between primary tumors Th- MYCN, Caspase-8 wild type with no BMM, and primary tumors Th-MYCN, deficient caspase-8 without BMM (p

The effect of 20 MeV electron radiation on the lifetime of the silicon carbide power MOSFETs was investigated. Accelerated constant voltage stress (CVS) was applied on the pristine and irradiated devices and time-to-breakdown ( T BD ) and charge-to-breakdown ( Q BD ) of gate oxide were extracted and compared. The effect of electron radiation on the device lifetime reduction can be observed at lower stress gate-to-source voltage ( V GS ) levels. The models of T BD and Q BD dependence on the initial gate current ( I G0 ) are proposed which can be used to describe the device breakdown behaviour. peerReviewed

The title diradical was synthesized and investigated by ESR and UV-vis spectroscopy. It was found to have a lifetime of weeks even in the presence of oxygen, and even survives brief heating in toluene up to about 60 °C. In the UV-vis spectrum, the diradical showed reversible thermochromic behavior in the -10 to 50 °C range. In the ESR spectrum, hyperfine analysis showed nearly isolated behavior by the phenoxyl and nitroxide spin carrying units. Upon warming, additional, broad lines appeared at the expense of the lower temperature lines. This temperature behavior was reversible over the 0 to 50 °C range, so long as the raised temperatures were not maintained for long time periods. The spectral behavior is interpreted as being due to temperature-dependent conformational effects on the exchange coupling between the spin carrying units, i.e.

A series of donor-acceptor (D–A) type conjugated molecules was synthesized, with structures D–π–A or A–π–D–π–A where A = N-hexylpyridinium-4-yl and D = electron donor type units, with A and D linked by π-conjugating units: the D–π–A systems are design-testing models for optimizing the A–π–D-π-A systems, where the latter are conjugatively extended variants of viologen. UV–vis absorption spectra and molar absorptivities were determined in varying solvents, and spectra for neat films. The donor units D comprised phenylene, 2,5-thienylene, 3,4-ethylenedioxythiophen-2,5-diyl (EDOT), 1-N-methyl-2,5-pyrrolediyl, and CH CH units. The system with strongest absorptivity at a relatively long absorption maximum and onset was the extended viologen 4-(1-hexyl)pyridinium-CH CH-(2,5-EDOT-CH CH-)-(2,5-thienylene-CH CH )-(2,5-EDOT-CH = CH-)-4-(1-hexyl)pyridinium dibromide, with λmax(methanol) = 576 nm (278,000 M−1 cm−1), low energy onset at 683 nm (1.82 eV). Photoluminescence quantum yields in methanol mostly were quite weak, with solvatochromic behavior indicating strong intramolecular charge transfer character.

The geometry and electronic structures of four cyclopentadithiophene (CPD) derivatives in their crystals are systematically studied through density functional theory (DFT) calculations. The factors influencing the CPDs' semiconductor nature and charge carrier mobility are analyzed in detail, revealing the different roles of fluorine and dicyanomethylene in the CPDs examined in this study. Malononitrile substitutions show a large effect in lowering the molecular LUMO energy level but induce a smaller charge transfer integral due to the resulting reduced crystal order caused by the resulting steric hindrance. In comparison, although F substitution lowers the LUMO level more weakly than C(CN)2 substitution, it allows the molecule to retain a more planar configuration with more orbital delocalization, and the crystals of the F substituted compounds are more ordered than those of the C(CN)2 substituted compounds. Overall, this comparison can explain why F substitution is a more effective method to cause a transition of a p-type semiconductor to n-type. Crystal ordering plays a significant role in determining the charge transfer mobility in devices. In spite of the advantage offered by dicyanomethylene substitution in terms of charge injection barrier compared to fluorine substitution, the reduced crystal order caused by C(CN)2 limits the charge transfer in CPDs with C(CN)2 substitution. The validity of these findings can be generalized, which is expected to contribute to the rational design of n-type semiconductors based on CPDs.

Lipid oxidation is one of the major causes of oil deterioration causing off-flavors and consumer rejection. Fast, easy, and dependable assays for predicting lipid oxidation rates in foods are important for shelf-life prediction. In this study, an electron paramagnetic resonance (EPR) spin-trapping technique with N-tert-butyl-α-phenylnitrone (PBN) was tested to determine the lag phase of lipid oxidation in stripped soybean oil (SSO), SSO with added α-tocopherol, and commercial soybean, canola and corn oils. EPR intensity of spin-trapped products from SSO correlated well with lipid hydroperoxides formation for samples stored at 37 and 55 °C respectively. When the antioxidant α-tocopherol was added, the EPR signal intensity of oil samples increased—indicating sample deterioration—after 50–65% of α-tocopherol was consumed. When using the EPR method with commercial soybean, canola or corn oil stored at 55 °C, there was a poor relationship between EPR intensity and lipid hydroperoxides lag phases. However, a linear correlation was found between EPR signal intensity and hexanal formation. For example, EPR signal intensity lag phases were 5, 13 and 27 days for soybean, canola and corn oils, respectively which was similar to the hexanal lag phases of 5, 13 and 25 days for the same oils. The EPR spin-trapping assay method has several advantages over headspace hexanal measurements, especially with regard to easier sample handling and shorter analysis times.

The first syntheses of bis(nitronyl nitroxide) and bis(iminoyl nitroxide) (diNN, diIN) biradicals linked through rigid acene core conjugating anthracene (A) and anthraquinone (AQ) units are reported. Computational modeling predicts weak intramolecular exchange in AQ-linked systems, but A-linked biradicals to have ground state multiplicities consistent with the Borden-Davidson disjointness model. Solution electron spin resonance spectra showed inter-radical exchange-coupled triplet states, except for 2,6-AQ biradicals showing isolated spin spectra. Crystallography of the A-linked biradicals shows a key role for inter-radical contacts for molecular packing. DiINs showed lower-dimensional dyad packing with disorder at the radical units: the conformationally more symmetrical diNNs gave staircase one-dimensional or brickwork two-dimensional lattices. Core anthracene unit stacking was only seen in two systems with bromine on the central anthracene ring: the (large) bromine occupies alternate side placement in d...

Binary polymer nanoparticle glasses provide opportunities to realize the facile assembly of disparate components, with control over nanoscale and mesoscale domains, for the development of functional materials. This work demonstrates that tunable electrical percolation can be achieved through semiconducting/insulating polymer nanoparticle glasses by varying the relative percentages of equal-sized nanoparticle constituents of the binary assembly. Using time-of-flight charge carrier mobility measurements and conducting atomic force microscopy, we show that these systems exhibit power law scaling percolation behavior with percolation thresholds of ∼24-30%. We develop a simple resistor network model, which can reproduce the experimental data, and can be used to predict percolation trends in binary polymer nanoparticle glasses. Finally, we analyze the cluster statistics of simulated binary nanoparticle glasses, and characterize them according to their predominant local motifs as (p(i), p(1-i))-connected networks that can be used as a supramolecular toolbox for rational material design based on polymer nanoparticles.

Eight cyclopentadithiophene (CPD) based semiconductors are designed by moving phenyl/fluorine-phenyl groups from α to β positions of thiophenes of CPD. The semiconductor performances of these CPD derivatives with Cs and C2 symmetry (termed as CPD’ and CPD’’, respectively) and their unsubstituted CPD backbones are analyzed systematically through DFT calculations. Some CPD’/CPD’’ compounds show better charge transfer mobility than CPD. We analyze in detail the factors influencing the semiconductor nature of these CPD derivatives and their charge carrier mobilities, revealing the different roles of fluorine and dicyanomethylene and of the α and β position of phenyl on the thiophene rings. Our findings can be generalized to broader classes of organic semiconductors and are expected to contribute to the rational design of n-type semiconductors based on CPDs.

Recent epidemiologic papers are presenting prevalence data suggesting breaks and decreases in obesity rates. However, before concluding that the obesity epidemic is not increasing anymore, the validity of the presented data should be discussed more thoroughly. We had a closer look into the literature presented in recent reviews to address the major potential biases and distortions, and to develop insights about how to interpret the presented suggestions for a potential break in the obesity epidemic. Decreasing participation rates, the use of reported rather than measured data and small sample sizes, or lack of representativeness, did not seem to explain presented breaks in the obesity epidemic. Further, available evidence does not suggest that stabilization of obesity rates is seen in higher socioeconomic groups only, or that urbanization could explain a potential break in the obesity epidemic. However, follow-ups of short duration may, in part, explain the apparent break or decrease in the obesity epidemic. On the other hand, a single focus on body mass index (BMI) ≥ 25 or ≥ 30 kgm-2 is likely to mask a real increase in the obesity epidemic. And, in both children and adults, trends in waist circumferences were generally suggesting an increase, and were stronger than those reported for trends in BMI. Studies concluding that there is a recent break in the obesity epidemic need to be interpreted with caution. Reported studies presenting a break were mostly of short duration. Further, focusing on trends in waist circumference rather than BMI leads to a less optimistic conclusion: the public health problem of obesity is still increasing.

We study the interaction between dibromobianthryl (DBBA) and the Ag(100) surface using scanning tunneling microscopy and density functional theory. DBBA is prochiral on adsorption and forms racemic domains with molecular rows aligned with the substrate nearest-neighbor [011] and [01¯1] directions. Deposition at elevated temperatures leads to the formation of disordered meandering graphene nanowires of constant width.

The chemisorption of tellurium on atomically clean Cu(111) surface has been studied under ultra-high vacuum conditions. At room temperature, the initial stage of growth was an ordered 2 3 × 2 3 R30° phase (0.08 ML). An ordered 3 × 3 R30° phase is formed at 0.33 ML coverage of Te. The adsorption sites of the Te atoms on the Cu(111) surface at 0.08 ML and 0.33 ML coverages are explored by quantitative low energy electron diffraction (LEED) and density functional theory (DFT). Our results indicate that substitutional surface alloy formation starts at very low coverages.

For environmentally friendly and cost-effective manufacturing of organic photovoltaic (OPV) cells, it is highly desirable to replace haloarenes with water as the active layer fabrication solvent. Replacing an organic solvent with water requires retooling the device fabrication steps. The optimization studies were conducted using poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61 butyric acid methyl ester (PCBM) as active layer materials. These materials were dispersed in water as blend and separate nanoparticles using the miniemulsion method. Topologies of the active layers were investigated using atomic force microscopy and electron microscopy techniques. We have identified two essential steps to fabricate efficient OPVs from aqueous dispersions: (1) treatment of the hole-transport layer with UV-O3 to make the surface hydrophilic and (2) the use of an electron-transporting buffer layer for efficient charge extraction. We have also identified relative humidity and substrate temperature as key fabrication parameters for obtaining uniform active layer films. The OPV devices were fabricated using PEDOT:PSS as the hole-transport layer and PCBM as electron-transport layer with Ca/Al as the counter electrode. Efficiencies of 2.15% with a fill factor over 66% were obtained; the efficiency and the fill-factor is the highest among all aqueous processing of P3HT–PCBM nanoparticle solar cells.

The ChlR1 DNA helicase is mutated in Warsaw breakage syndrome characterized by developmental anomalies, chromosomal breakage, and sister chromatid cohesion defects. However, the mechanism by which ChlR1 preserves genomic integrity is largely unknown. Here, we describe the roles of ChlR1 in DNA replication recovery. We show that ChlR1 depletion renders human cells highly sensitive to cisplatin; an interstrand-crosslinking agent that causes stalled replication forks. ChlR1 depletion also causes accumulation of DNA damage in response to cisplatin, leading to a significant delay in resolution of DNA damage. We also report that ChlR1-depleted cells display defects in the repair of double-strand breaks induced by the I-PpoI endonuclease and bleomycin. Furthermore, we demonstrate that ChlR1-depeleted cells show significant delays in replication recovery after cisplatin treatment. Taken together, our results indicate that ChlR1 plays an important role in efficient DNA repair during DNA replication, which may facilitate efficient establishment of sister chromatid cohesion.

2-(3′,5′-Dimethoxy-4′-hydroxyphenyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-1-oxyl (SyrNN) forms a hydrogen bonded network of contacts involving phenolic OH and nitronylnitroxide methyl groups as donors, and nitronylnitroxide NO groups as acceptors. The SyrNN intermolecular contact network is quite similar to that of 2-(4′-hydroxyphenyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-1-oxyl (HOPhNN) (Cirujeda et al., J. Mater. Chem. 1995, 5, 243–252), which shows ferromagnetic exchange interactions, but SyrNN has an additional antiparallel stacking contact between nitronylnitroxide NO groups that qualitatively and computationally is expected to induce antiferromagnetic (AFM) exchange between SyrNN molecules. Experimentally, the magnetism of SyrNN shows evidence of multiple exchange interactions with overall low dimensional AFM exchange behavior. Fits of dc magnetic susceptibility versus temperature data for SyrNN to AFM 1-D chain and 2-D square planar models give J/k ∼ (−)1–3 K.

Surface ordering of pentacene molecules adsorbed on an aperiodic Cu surface has been studied with density functional theory (DFT) and scanning tunnelling microscopy as a function of coverage. Below 0.73 ML (5.3 × 1013 molecules cm−2), the adsorbate structure is row-like with the molecular axes aligned with the rows in the Cu structure. Between this coverage and 1 ML (7.3 × 1013 molecules cm−2), a structural phase with a checkerboard structure is seen. At this coverage region, the molecules are very close to each other which leads to unusual bending. At higher coverages, a further phase transition to a high-density row structure is seen for most of the film. DFT with van der Waals functionals is employed to study how the molecule-molecule and molecule-surface interactions evolve as a function of coverage.

The atomic structures that develop as a function of coverage during deposition of Bi on Ag(111) have been studied using low-temperature scanning tunneling microscopy, low-energy electron diffraction, and ab initio calculations. The growth process involves two sequential stages. At low coverage, Bi atoms are incorporated into the topmost layer of Ag(111), resulting in the formation of an Ag${}_{2}$Bi alloy confined to the surface and ordered ($\sqrt{3}\ifmmode\times\else\texttimes\fi{}\sqrt{3}$)$R$30\ifmmode^\circ\else\textdegree\fi{} Ag${}_{2}$Bi islands supported on Ag(111). This mode of accommodation of Bi was found to be energetically favorable based on ab initio total-energy calculations. At coverage above a critical value of 0.55 monolayers, the Ag${}_{2}$Bi alloy phase gradually converts into an ordered Bi ($p\ifmmode\times\else\texttimes\fi{}\sqrt{3}$) overlayer structure supported on Ag(111). We postulate that the dealloying transition is likely driven by compressive strain induced by incorporation of large-size Bi atoms into Ag at a high coverage and the subsequent lack of miscibility of Ag and Bi bulk phases. After completion of the dealloying process, Bi(110) thin films can be grown epitaxially on top of Ag(111) with a chemically abrupt interface.

In this contribution, we report on the electronic energy transfer dynamics of bichromophoric systems incorporating two pyrene chromophores tethered by variable-length flexible alkyloxy chains to p-phenylenevinylene oligomers. These were studied using UV-vis absorption and both steady state and time-resolved fluorescence spectroscopy. Time-resolved emission measurements showed an efficient photoinduced energy transfer process in all the multichromophoric systems, which occurs on the time scale of tens of picoseconds after excitation at 265 nm. The energy transfer process is especially efficient in systems where the linker is formed by eight atoms (up to k(ET) ≈ 2.7 × 10(10) s(-1)), which, despite not being the shortest bridge studied, allows the approach of the donor and acceptor chromophores due to an appropriate number of flexible single bonds. Using Förster theory, we calculated the donor-acceptor distance in each triad from the experimental energy transfer rate, finding them to be in the range 8.8-10 Å.

Tetraspanin CD151 is highly expressed in endothelial cells and regulates pathologic angiogenesis. However, the mechanism by which CD151 promotes vascular morphogenesis and whether CD151 engages other vascular functions are unclear. Here we report that CD151 is required for maintaining endothelial capillary-like structures formed in vitro and the integrity of endothelial cell-cell and cell-matrix contacts in vivo. In addition, vascular permeability is markedly enhanced in the absence of CD151. As a global regulator of endothelial cell-cell and cell-matrix adhesions, CD151 is needed for the optimal functions of various cell adhesion proteins. The loss of CD151 elevates actin cytoskeletal traction by up-regulating RhoA signaling and diminishes actin cortical meshwork by down-regulating Rac1 activity. The inhibition of RhoA or activation of cAMP signaling stabilizes CD151-silenced or -null endothelial structure in vascular morphogenesis. Together, our data demonstrate that CD151 maintains vascular stability by promoting endothelial cell adhesions, especially cell-cell adhesion, and confining cytoskeletal tension.

9-(N,N-Dianisylamino)anthracene (9DAAA), 9-(N,N-dianisylamino)dinaphth([1,2-a:2'-1'-j]-anthracene (9DAAH), and 9,10-bis(N,N-dianisylamino)anthracene (910BAA) were synthesized as highly twisted triarylamines with potential for photoexcited internal charge transfer. Crystallography of 9DAAA shows its dianisylamino group to be twisted nearly perpendicular to its anthracene unit, similar to a report for 910BAA. The solution fluorescence spectra show strong bathochromic shifts for each of the three molecular systems with strongly decreased quantum efficiency in higher polarity solvents. Solution-phase (ensemble) time-resolved photoluminescence measurements show up to 4-fold decreases in fluorescence lifetime in acetonitrile compared to hexane. The combined results are consistent with photoinduced, transient intramolecular charge-transfer from the bis-anisylamine unit to the polycyclic aromatic unit. Computational modeling is in accord with intramolecular transfer of electron density from the bis-anisylamino unit to the anthracene, based on in comparisons of HOMO and LUMO.

Hydroxycarbamide (hydroxyurea) provides laboratory and clinical benefits for adults and children with sickle cell anaemia (SCA). Given its mechanism of action and prior reports of genotoxicity, concern exists regarding long-term toxicities and possible carcinogenicity. We performed cross-sectional analyses of chromosome stability using peripheral blood mononuclear cells (PBMC) from 51 children with SCA and 3-12 years of hydroxycarbamide exposure (mean age 13·2 ± 4·1 years), compared to 28 children before treatment (9·4 ± 4·7 years). Chromosome damage was less for children receiving hydroxycarbamide than untreated patients (0·8 ± 1·2 vs. 1·9 ± 1·5 breaks per 100 cells, P = 0·004). There were no differences in repairing chromosome breaks after in vitro radiation; PBMC from children taking hydroxycarbamide had equivalent 2 Gy-induced chromosome breaks compared to untreated patients (30·8 ± 16·1 vs. 31·7 ± 8·9 per 100 cells, P = not significant). Radiation plus hydroxycarbamide resulted in similar numbers of unrepaired breaks in cells from children on hydroxycarbamide compared to untreated patients (95·8 ± 44·2 vs. 76·1 ± 23·1 per 100 cells, P = 0·08), but no differences were noted with longer exposure (97·9 ± 42·8 breaks per 100 cells for 3-6 years of hydroxycarbamide exposure vs. 91·2 ± 48·4 for 9-12 years of exposure). These observations provide important safety data regarding long-term risks of hydroxycarbamide exposure for children with SCA, and suggest low in vivo mutagenicity and carcinogenicity.

Background Demethylating agents may alter the expression of genes involved in chemotherapy resistance. We conducted a phase I trial to determine the toxicity and molecular effects of the demethylating agent, decitabine, followed by doxorubicin and cyclophosphamide in children with refractory solid tumors. Procedure Stratum A included children with any solid tumor; Stratum B included neuroblastoma patients only. Patients received a 1-hr decitabine infusion for 7 days, followed by doxorubicin (45 mg/m2) and cyclophosphamide (1 g/m2) on day 7. Pharmacokinetic studies were performed after the first dose of decitabine. Biological studies included methylation and gene expression analyses of caspase-8, MAGE-1 and fetal hemoglobin (HbF), and expression profiling of pre- and post-treatment peripheral blood and bone marrow cells. Results The maximum-tolerated dose of decitabine was 5 mg/m2/day for 7 days. Dose-limiting toxicities at 10 mg/m2/day were neutropenia and thrombocytopenia. Decitabine exhibited rapid clearance from plasma. Three of 9 patients in Stratum A and 4/12 patients in Stratum B had stable disease for ≥4 months. Sustained MAGE-1 demethylation and increased HbF expression were observed in the majority of patients post-treatment (12/20 and 14/16, respectively). Caspase-8 promoter demethylation and gene expression were seen in 2/7 bone marrow samples. Differentially expressed genes were identified by microarray analysis. Conclusion Low-dose decitabine when combined with doxorubicin/cyclophosphamide has tolerable toxicity in children. However, doses of decitabine capable of producing clinically relevant biologic effects were not well tolerated with this combination. Alternative strategies of combining demethylating agents with non-cytotoxic, biologically targeted agents such as histone deactelyase inhibitors should be explored. Pediatr Blood Cancer. 2010;55:629–638. © 2010 Wiley-Liss, Inc.

This study reports on a dual drug-eluting stent (DDES) that has an anti-proliferative and an anti-thrombotic in a biodegradable polymer-coated onto a cobalt-chromium stent. The DDES was prepared by spray coating the bare metal stent with a biodegradable polymer loaded with sirolimus and triflusal, to treat against restenosis and thrombosis, respectively. The 2-layered dual-drug coated stent was characterized in vitro for surface properties before and after expansion, as well as for possible delamination by cross-sectioning the stent in vitro. The in vitro anti-platelet behavior of the triflusal-loaded films was investigated by using dynamic platelet adhesion measurements. Additionally, the in vitro degradation and release study of the films and the stents w/single sirolimus and dual sirolimus-triflusal in different formulations were examined. Finally, in vivo studies (in a porcine carotid artery model) were performed for acute thrombosis, inflammation and restenosis at 30 days. The in vitro results show DDES can sustain release both anti-proliferation drug (sirolimus) and anti-thrombosis drug (triflusal), two drugs were controlled in different rates to effectively reduce thrombosis and proliferation at the same time. In vivo results show a significant reduction in restenosis with dual-drug eluting stent compared with the controls (a bare metal stent, a sirolimus coated and a pure polymer-coated stent). The reduction in restenosis with a dual sirolimus-triflusal eluting stent is associated with an inhibition of inflammation, especially thrombus formation, suggesting that such dual-drug eluting stents have a role to play for the treatment of coronary artery disease.

This paper describes the airborne electromagnetic (AEM) system operated by the Joint Airborne geoscience Capability (JAC), a partnership between the Finnish and British Geological Surveys. The system is a component of a 3-in-1, fixed-wing facility acquiring magnetic gradiometer and full spectrum radiometric data alongside the wing-tip, frequency-domain AEM measurements. The AEM system has recently (2005) been upgraded from 2 to 4 frequencies and now provides a bandwidth from 900 Hz to 25 kHz. The fixed-wing configuration of 4 dual vertical coplanar coils, offers a high signal/noise by virtue of the wingspan separation of the sensors. This unique configuration allows 3-in-1 surveys to be successfully performed at a variety of survey elevations when regulatory conditions are imposed. Its deployment on a twin-engine aircraft also permits low altitude surveying in countries, such as the UK, where this is a requirement. The development of the new AEM-05 system has been incremental and its history can be traced back over five decades. The AEM data acquired in the Finnish National Mapping project, and across northern Europe, have been used extensively in mineral exploration. More recent projects have investigated the application of the data to environmental, hydrogeological and land quality issues. These studies have been enhanced by reducing the flight line separation from 200 m (the national high-resolution scale) to 50 m. Our surveys also increasingly involve the application of AEM across populated areas often with extensive infrastructure. Additional secondary instrumentation has been introduced to provide an increased understanding of the data and the AEM responses observed. The secondary systems include an accurate, high sampling rate laser altimeter, a downward-looking digital camera to record the flight path, a 50/60 Hz power line monitor and a GPS gyroscope. The paper is intended as an overview and provides descriptions of the new AEM system, the secondary systems now employed and some of the software used to provide accurate and levelled AEM data. Recent applications of the system are reviewed and the challenging nature of the new subsurface information being revealed is demonstrated.

Arf, Hdm2 and p53 regulate the tumor suppressor pathway that is most frequently disrupted in human cancer. In the absence of tumorigenic stress, Hdm2 actively attenuates p53-dependent cell cycle arrest and apoptosis by mediating ubiquitination-dependent degradation of p53. Mitogenic stress activates Arf, which indirectly activates p53 by binding to and nullifying the anti-p53 activities of Hdm2. Small, conserved domains within Arf and Hdm2 mediate their direct interaction. Individually, these domains are intrinsically unstructured and, when combined in vitro, they co-fold into bi-molecular oligomeric structures that, in some features, resemble amyloid fibrils. Detailed structural characterization of Arf/Hdm2 complexes has previously been hampered by their heterogeneity and large size. Here, we report that a 9-residue fragment of the N-terminus of mouse Arf (termed A1-mini) co-folds specifically with the Arf-binding domain of Hdm2 to form bi-molecular oligomers. We characterized these unprecedented structures using analytical ultracentrifugation and NMR spectroscopy, providing insights into their structural organization. The A1-mini peptide not only binds specifically to Hdm2 in vitro, but also recapitulates the nucleolar localization features of full-length Arf in cells. Further, larger fragments of Arf that contain the A1-mini segment have previously been shown to activate p53 in mouse and human cells. Our studies provide the first insights into the molecular basis through which Arf nullifies the p53-inhibiting activity of Hdm2, indirectly activating the tumor suppressor function of p53 in mammalian cells.

The heat capacity of the title organic free radical, PhBABI, was measured over 0.3-300 K by adiabatic calorimetry and relaxation methods in the presence of external magnetic fields up to 9 T. A hump in the magnetic heat capacity was observed with a maximum at about 15 K in zero field, which did not shift at fields up to 9 T. The experimental magnetic entropy was in good agreement with the theoretical value of R ln 2 (= 5.76 J K(-1) mol(-1)) for S = 1/2 systems. The higher temperature, field-insensitive feature was fitted to several antiferromagnetic Heisenberg models. The best fits were obtained using spin ladder and coupled spin bilayer models.

The photochemistry of azidopyridine 1-oxides was studied using an array of glass and matrix isolation techniques. As with room temperature, the photochemistry of 4-azidopyridine 1-oxide is dominated by triplet nitrene chemistry. However, in the case of the 3-azide, matrix photolysis indicates the formation of diazabicyclo[4.1.0]hepta-2,4,6-triene N-oxide and diazacycloheptatetraene N-oxide intermediates as well as triplet nitrene.

Although epithelial morphogenesis is tightly controlled by intrinsic genetic programs, the microenvironment in which epithelial cells proliferate and differentiate also contributes to the morphogenetic process. The roles of the physical microenvironment in epithelial morphogenesis, however, have not been well dissected. In this study, we assessed the impact of the microenvironment on epithelial cyst formation, which often marks the beginning or end step of morphogenesis of epithelial tissues and the pathological characteristic of some diseases. Previous studies have demonstrated that Madin-Darby canine kidney (MDCK) epithelial cells form cysts when grown in a three-dimensional (3D) extracellullar matrix (ECM) environment. We have now further demonstrated that the presence of ECM in the 3D scaffold is required for the formation of properly polarized cysts. Also, we have found that the full interface of epithelial cells with the ECM environment (in-3D) is not essential for cyst formation, since partial contact (on-3D) is sufficient to induce cystogenesis. In addition, we have defined the minimal ECM environment or the physical threshold for cystogenesis under the on-3D condition. Only above the threshold can the morphological cues from the ECM environment induce cyst formation. Moreover, cyst formation under the on-3D condition described in this study defines a novel and more feasible model to analyze in vitro morphogenesis. Finally, we have found that, during cystogenesis, MDCK cells generate basal microprotrusions and produce vesicle-like structures to the basal extracellular space, which are specific to and correlated with cyst formation. For the first time, we have systematically and quantitatively elucidated the microenvironmental determinants for epithelial cystogenesis.

Although it has been reported that cyclin L1α and L2α proteins interact with CDK11p110, the nature of the cyclin L transcripts, the formation of complexes between the five cyclin L and the three CDK11 protein isoforms, and the influence of these complexes on splicing have not been thoroughly investigated. Here we report that cyclin L1 and L2 genes generate 14 mRNA variants encoding six cyclin L proteins, one of which has not been described previously. Using cyclin L gene-specific antibodies, we demonstrate expression of multiple endogenous cyclin L proteins in human cell lines and mouse tissues. Moreover, we characterize interactions between CDK11p110, mitosis-specific CDK11p58, and apoptosis-specific CDK11p46 with both cyclin Lα and -β proteins and the co-elution of these proteins following size exclusion chromatography. We further establish that CDK11p110 and associated cyclin Lα/β proteins localize to splicing factor compartments and nucleoplasm and interact with serine/arginine-rich proteins. Importantly, we also determine the effect of CDK11-cyclin L complexes on pre-mRNA splicing. Preincubation of nuclear extracts with purified cyclin Lα and -β isoforms depletes the extract of in vitro splicing activity. Ectopic expression of cyclin L1α, L1β, L2α, or L2β or active CDK11p110 individually enhances intracellular intron splicing activity, whereas expression of CDK11p58/p46 or kinase-dead CDK11p110represses splicing activity. Finally, we demonstrate that expression of cyclins Lα and -β and CDK11p110 strongly and differentially affects alternative splicing in vivo. Together, these data establish that CDK11p110 interacts physically and functionally with cyclin Lα and -β isoforms and SR proteins to regulate splicing.

Solar cells fabricated using alkyl ammonium metal halides as light absorbers have the right combination of high power conversion efficiency and ease of fabrication to realize inexpensive but efficient thin film solar cells. However, they degrade under prolonged exposure to sunlight. Herein, we show that this degradation is quasi-reversible, and that it can be greatly lessened by simple modifications of the solar cell operating conditions. We studied perovskite devices using electrochemical impedance spectroscopy (EIS) with methylammonium (MA)-, formamidinium (FA)-, and MA(x)FA(1-x) lead triiodide as active layers. From variable temperature EIS studies, we found that the diffusion coefficient using MA ions was greater than when using FA ions. Structural studies using powder X-ray diffraction (PXRD) show that for MAPbI3 a structural change and lattice expansion occurs at device operating temperatures. On the basis of EIS and PXRD studies, we postulate that in MAPbI3 the predominant mechanism of accelerated device degradation under sunlight involves thermally activated fast ion transport coupled with a lattice-expanding phase transition, both of which are facilitated by absorption of the infrared component of the solar spectrum. Using these findings, we show that the devices show greatly improved operation lifetimes and stability under white-light emitting diodes, or under a solar simulator with an infrared cutoff filter or with cooling.

Rigid–flexible segmented block copolymers were synthesized and characterized as 4.5-oligophenylenevinylene chromophores tethered by flexible, conjugation-interrupting 1,2-ethanedioxy or 1,4-butanedioxy units. The flexible tethers allow the possibility of collapsed order chromophore assemblies within individual polymers by chain folding at specific sites much like an old fashioned, folding carpenter’s rule. Our results indicate that using a short, flexible tether in a rigid–flexible segmented copolymer can result in collapsed rodlike structures as signaled by strongly quenched photoluminescence, even after thermal annealing. Such ability to “program” folding and tertiary structure in conjugated copolymers is important for solid-state organic light emitting materials and understanding of organic chromophore self-assembly.

A set of Don --Acc-- Don multichromophores was synthesized based on a simple design with two pyrene donors (absorbing antennae) connected to a bis-1,4-(3,4,5-trimethoxystyryl)benzene core acceptor using various flexible, nonconjugated tethers. Excitation of the pyrene donors at 276 nm in solution yields near exclusive emission from the core chromophore at 445-450 nm, with energy transfer efficiencies up to 92%, far better than achieved with simple mixtures. The simple tethering design imposes a high "local" concentration of the pyrene near the acceptor core unit that is maintained even at very low multichromophore concentrations. Solvent effects on absorption and emission spectra are very small, except in cases where a pi-conjugating O-C=O moiety of the tethering group is directly attached to the core chromophore, rather than being placed in the middle of the tether. Energy transfer in the systems is effective due to good donor-acceptor energy matching. The optimal energy transfer efficiency was achieved using an eight-atom flexible linker.