Rapid reaction optimization by robust and economical quantitative benchtop 19F NMR spectroscopy

The instrumental analysis of reaction mixtures is usually the rate-determining step in the optimization of chemical processes. Traditionally, reactions are analyzed by gas chromatography, HPLC or quantitative NMR spectroscopy on high-field spectrometers. However, chromatographic methods require elaborate work-up and calibration protocols, and high-field NMR spectrometers are expensive to purchase and operate. This protocol describes an inexpensive and highly effective analysis method based on low-field benchtop NMR spectroscopy. Its key feature is the use of fluorine-labeled model substrates that, because of the wide chemical shift range and high sensitivity of 19F, enable separate, quantitative detection of product and by-product signals even on low-field, permanent magnet spectrometers. An external lock/shim device obviates the need for deuterated solvents, permitting the direct, noninvasive measurement of crude reaction mixtures with minimal workup. The low field-strength facilitates a homogeneous excitation over a wide chemical shift range, minimizing systematic integration errors. The addition of the optimal amount of the nonshifting relaxation agent tris(acetylacetonato) iron(III) minimizes relaxation delays at full resolution, reducing the analysis time to 32 s per sample. The correct choice of processing parameters is also crucial. A step-by-step guideline is provided, the influence of all parameters, including adjustments needed when using high-field spectrometers, is discussed and potential pitfalls are highlighted. The wide applicability of the analytical protocol for reaction optimization is illustrated by three examples: a Buchwald-Hartwig amination, a Suzuki coupling and a C-H arylation reaction.

Analytic Form of the Full Two-Loop Five-Gluon All-Plus Helicity Amplitude

We compute the full-color two-loop five-gluon amplitude for the all-plus helicity configuration. In order to achieve this, we calculate the required master integrals for all permutations of the external legs, in the physical scattering region. We verify the expected divergence structure of the amplitude and extract the finite hard function. We further validate our result by checking the factorization properties in the collinear limit. Our result is fully analytic and valid in the physical scattering region. We express it in a compact form containing logarithms, dilogarithms, and rational functions.

Abstract GS5-03: Lifestyle Intervention and Effect on Disease-free Survival in Early Breast Cancer Pts: Interim Analysis from the Randomized SUCCESS C Study

Background:

Recent trials have provided evidence that obesity and a low level of physical activity are not only associated with a higher risk of developing breast cancer, but also with an increased risk for recurrence and reduced survival in breast cancer patients (pts). The SUCCESS C study is the first randomized Phase III trial to evaluate the effect of an intensive lifestyle intervention program, focusing on both physical activity and healthy diet following adjuvant chemotherapy on disease-free survival in women with early breast cancer.

Methods:

SUCCESS C is a German multicenter, 2×2 factorial design, randomized phase III study comparing disease-free survival (DFS) in pts with HER2-negative early breast cancer treated with either 3 cycles of epirubicine, fluorouracil, cyclophosphamide chemotherapy followed by 3 cycles of docetaxel (FEC-D) or 6 cycles of docetaxel-cyclophosphamide (DC). The second randomization compares DFS in pts with a body mass index (BMI) of 24—40 kg/m2 receiving either a telephone-based individualized lifestyle intervention (LI) program aiming at moderate weight loss for 2 years (LI arm) or general recommendations for a healthy lifestyle alone (non-LI arm). DFS according to lifestyle intervention was analyzed using both univariable cox regressions and multivariable cox regressions adjusted for age (years, continuous), BMI (kg/m2, continuous), menopausal status (premenopausal, postmenopausal), tumor size (pT1, pT2, pT3/pT4), nodal stage (pN0, pN1, pN2, pN3), hormone receptor status (positive, negative), grading (G1, G2, G3), histological type (ductal, lobular, other) and chemotherapy randomization (FEC-D, DC). Median follow-up was 64.2 months.

Results:

Overall, 2292 of the 3643 pts recruited for the SUCCESS C study were randomized for the lifestyle intervention program (1146 pts in both the non-LI arm and the LI arm). The Intention-to-treat analysis revealed no difference in DFS between the two treatment arms (LI vs. non-LI) in univariable analysis (hazard ratio [HR] 0.99, 95% confidence interval [CI] 0.76 — 1.28, p = 0.922) and in adjusted multivariable cox regression (HR 0.91, 95% CI 0.70 — 1.18, p = 0.48). At the 2-year follow up, pts in the LI arm lost on average 1.0 kg weight compared to the start of the LI program, while pts in the non-LI arm gained on average 0.95 kg (p < 0.001). Overall, 1477 pts completed the 2-year LI program (non-LI arm: 80.7%, 925 of 1146 pts; LI arm: 48.2%, 552 of 1146 pts; p < 0.001). Pts that completed the 2-year LI program had a significant better DFS than non-completers (HR 0.35, 95% CI 0.27 — 0.45, p < 0.001). Among completers, pts in the LI arm had a significantly better DFS than pts in the non-LI arm both in univariable analysis (HR 0.53, 95% CI 0.35 — 0.82, p = 0.004) and in adjusted multivariable cox regression (HR 0.51, 95% CI 0.33 — 0.78, p = 0.002).

Conclusions:

This explorative and non-planned interim analysis indicates that the completion of a systematic telephone life style intervention program may positively impact patient outcome in early breast cancer.

Citation Format: Janni W, Rack BK, Friedl TW, Müller V, Lorenz R, Rezai M, Tesch H, Heinrich G, Andergassen U, Harbeck N, Schochter F, De Gregorio A, Tzschaschel M, Huober J, Hepp P, Fehm TN, Schneeweiss A, Lichtenegger W, Blohmer J, Hauner D, Beckmann MW, Häberle L, Fasching PA, Hauner H. Lifestyle Intervention and Effect on Disease-free Survival in Early Breast Cancer Pts: Interim Analysis from the Randomized SUCCESS C Study [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr GS5-03.

Influence of Electron Induced Reactive Processing and Secondary Rubber Phase on Spinnability of Polypropylene and Polypropylene/Rubber Blends

The melt spinning behavior of electron-irradiated polypropylene (PP) and PP/ethylene-octene-copolymer (EOC) blends was studied. The low ability to fiber formation of the impact enhanced PP/EOC blends with 2.5 mass percent of high viscous and non-spinnable EOC rubber was enhanced to a large extent by applying a dose of 6 kGy using a continuous electron induced reactive processing (CEIReP). The influence of structure alteration during CEIReP on the fiber formation as well as the textile physical properties of as-spun blend fiber were explored. A remarkable enhancement of the initial modulus as well as the linear elastic region of CEIReP modified PP/EOC blend fiber were achieved.

Rubber contact mechanics: adhesion, friction and leakage of seals

We study the adhesion, friction and leak rate of seals for four different elastomers: Acrylonitrile Butadiene Rubber (NBR), Ethylene Propylene Diene (EPDM), Polyepichlorohydrin (GECO) and Polydimethylsiloxane (PDMS). Adhesion between smooth clean glass balls and all the elastomers is studied both in the dry state and in water. In water, adhesion is observed for the NBR and PDMS elastomers, but not for the EPDM and GECO elastomers, which we attribute to the differences in surface energy and dewetting. The leakage of water is studied with rubber square-ring seals squeezed against sandblasted glass surfaces. Here we observe a strongly non-linear dependence of the leak rate on the water pressure ΔP for the elastomers exhibiting adhesion in water, while the leak rate depends nearly linearly on ΔP for the other elastomers. We attribute the non-linearity to some adhesion-related phenomena, such as dewetting or the (time-dependent) formation of gas bubbles, which blocks fluid flow channels. Finally, rubber friction is studied at low sliding speeds using smooth glass and sandblasted glass as substrates, both in the dry state and in water. The measured friction coefficients are compared to theory, and the origin of the frictional shear stress acting in the area of real contact is discussed. The NBR rubber, which exhibits the strongest adhesion both in the dry state and in water, also shows the highest friction both in the dry state and in water.

Genetic Breast Cancer Susceptibility Variants and Prognosis in the Prospectively Randomized SUCCESS A Study

Large-scale genotyping studies have identified over 70 single nucleotide polymorphisms (SNPs) associated with breast cancer (BC) risk. However, knowledge regarding genetic risk factors associated with the prognosis is limited. The aim of this study was therefore to investigate the prognostic effect of nine known breast cancer risk SNPs. BC patients (n = 1687) randomly sampled in an adjuvant, randomized phase III trial (SUCCESS A study) were genotyped for nine BC risk SNPs: rs17468277 (CASP8) , rs2981582 (FGFR2) , rs13281615(8q24), rs3817198 (LSP1) , rs889312 (MAP3K1) , rs3803662 (TOX3) , rs13387042(2q35), rs4973768 (SLC4A7) , rs6504950 (COX11) . Cox proportional hazards models were used to test the SNPs' association with overall survival (OS) and progression-free survival (PFS). Additional analyses were carried out for molecular subgroups. rs3817198 in LSP1 (lymphocyte-specific protein 1) was the only SNP that significantly influenced OS (p = 0.01) and PFS (p < 0.01) in the likelihood ratio test comparing the genetic survival model with the clinical survival model. In the molecular subgroups, triple-negative patients with two minor alleles in rs3817198 had a much better prognosis relative to OS (adjusted HR 0.03; 95% CI 0.002 - 0.279) and PFS (HR 0.09; 95% CI 0.02 - 0.36) than patients with the common alleles. The same effect on PFS was shown for patients with luminal A tumors (HR 0.19; 95% CI 0.05 - 0.84), whereas patients with luminal B tumors had a poorer PFS with two minor alleles (HR 2.13; 95% CI 1.02 - 4.40). The variant in rs3817198 has a prognostic effect particularly in the subgroup of patients with triple-negative BC, suggesting a possible link with immunomodulation and BC.

The HER2 phenotype of circulating tumor cells in HER2-positive early breast cancer: A translational research project of a prospective randomized phase III trial

Background

HER2 is one of the predominant therapeutic targets in breast cancer. The metastatic selection process may lead to discrepancies between the HER2 status of the primary tumor and circulating tumor cells (CTCs). This study analyzed the HER2 status of CTCs in patients with HER2-positive primary breast cancer at the time of diagnosis. Aim of the study was to assess potential discordance of HER2 status between primary tumor and CTCs, as this may have important implications for the use of HER2-targeted therapy.

Methods

The number and HER2 status of CTCs out of 30ml peripheral blood were assessed in 642 patients using the CellSearch System (Janssen Diagnostics, USA). The cutoff for CTC positivity was the presence of at least 1 CTC, and the cutoff for HER2 positivity of CTCs was the presence of at least 1 CTC with a strong HER2 staining.

Results

258 (40.2%) of the 642 patients were positive for CTCs (median 2; range 1–1,689). 149 (57.8%) of these 258 patients had at least 1 CTC with strong HER2 staining. The presence of HER2-positive CTCs was not associated with tumor size (p = 0.335), histopathological grading (p = 0.976), hormone receptor status (ER: p = 0.626, PR: p = 0.263) or axillary lymph node involvement (p = 0.430). Overall, 83 (32.2%) of the CTC-positive patients exclusively had CTCs with strong HER2 staining, whereas 31 (12.0%) had only CTCs with negative HER2 staining. Within-sample variation in the HER2 status of CTCs was found in 86 (57.8%) of the 149 patients with more than 1 CTC.

Conclusion

This study demonstrated that discordance between the HER2 expression of CTCs and that of the primary tumor frequently occurs in early breast cancer. Future follow-up evaluation will assess whether this discrepancy may contribute to trastuzumab resistance.

Filler flocculation in polymers - a simplified model derived from thermodynamics and game theory

The performance of elastomeric materials, i.e. in car tires, is substantially determined by the used reinforcing filler system. In particular, the flocculation tendency of filler particles to form clusters and even network-like structures significantly determines the mechanical properties of these elastomer materials and enhances especially their energy dissipation under periodic mechanical deformations. In a simplified thermodynamic model, inspired by a segregation model from game theory, we describe fundamental mechanisms of filler structure formation. As the final goal of this paper we want to demonstrate how similar structures in society, nature or materials like rubbers emerge when supposing obvious cardinal mechanisms of structure formation in complex systems.

The effect of surface roughness and viscoelasticity on rubber adhesion

Adhesion between silica glass or acrylic balls and silicone elastomers and various industrial rubbers is investigated. The work of adhesion during pull-off is found to strongly vary depending on the system, which we attribute to the two opposite effects: (1) viscoelastic energy dissipation close to an opening crack tip and (2) surface roughness. Introducing surface roughness on the glass ball is found to increase the work of adhesion for soft elastomers, while for the stiffer elastomers it results in a strong reduction in the work of adhesion. For the soft silicone elastomers a strong increase in the work of adhesion with increasing pull-off velocity is observed, which may result from the non-adiabatic processes associated with molecular chain pull-out. In general, the work of adhesion is decreased after repeated contacts due to the transfer of molecules from the elastomers to the glass ball. Thus, extracting the free chains (oligomers) from the silicone elastomers is shown to make the work of adhesion independent of the number of contacts. The viscoelastic properties (linear and nonlinear) of all of the rubber compounds are measured, and the velocity dependent crack opening propagation energy at the interface is calculated. Silicone elastomers show a good agreement between the measured work of adhesion and the predicted results, but carbon black filled hydrogenated nitrile butadiene rubber compounds reveal that strain softening at the crack tip may play an important role in determining the work of adhesion. Additionally, adhesion measurement under submerged conditions in distilled water and water + soap solutions are also performed: a strong reduction in the work of adhesion is measured for the silicone elastomers submerged in water, and a complete elimination of adhesion is found for the water + soap solution attributed to an osmotic repulsion between the negatively charged surface of the glass and the elastomer.

Erratum: Higgs Boson Pair Production in Gluon Fusion at Next-to-Leading Order with Full Top-Quark Mass Dependence [Phys. Rev. Lett. 117, 012001 (2016)]

This corrects the article DOI: 10.1103/PhysRevLett.117.012001.

Higgs Boson Pair Production in Gluon Fusion at Next-to-Leading Order with Full Top-Quark Mass Dependence

We present the calculation of the cross section and invariant mass distribution for Higgs boson pair production in gluon fusion at next-to-leading order (NLO) in QCD. Top-quark masses are fully taken into account throughout the calculation. The virtual two-loop amplitude has been generated using an extension of the program GoSam supplemented with an interface to Reduze for the integral reduction. The occurring integrals have been calculated numerically using the program SecDec. Our results, including the full top-quark mass dependence for the first time, allow us to assess the validity of various approximations proposed in the literature, which we also recalculate. We find substantial deviations between the NLO result and the different approximations, which emphasizes the importance of including the full top-quark mass dependence at NLO.

Study of Dispersive and Distributive Mixing in a Converging Pipe

The creeping flow of a polymeric melt in a converging pipe is analyzed using an in-house finite element code. An introduced power-law model considers the shear thinning behavior of the viscous liquid. Furthermore, distributive and dispersive mixing processes are evaluated with the mean strain function and the Manas-Zloczower mixing index, respectively. Using a parametric study, the dependency of the mixing criteria on the rheological and geometrical factors is investigated. Finally, a new analytical expression for the evaluation of the distributive mixing is suggested, based on simplifying assumptions and a curve fitting method.

Improvement of mechanical performance of solution styrene butadiene rubber by controlling the concentration and the size of in situ derived sol–gel silica particles

The silica particles generated from alkoxide route are grown onto the styrene butadiene polymer chains and offer a direct rubber to filler interaction. As a result, superior mechanical performance of the elastomeric composites can be realised.

Renormalization scheme dependence of the two-loop QCD corrections to the neutral Higgs-boson masses in the MSSM

Reaching a theoretical accuracy in the prediction of the lightest MSSM Higgs-boson mass, [Formula: see text], at the level of the current experimental precision requires the inclusion of momentum-dependent contributions at the two-loop level. Recently two groups presented the two-loop QCD momentum-dependent corrections to [Formula: see text] (Borowka et al., Eur Phys J C 74(8):2994, 2014; Degrassi et al., Eur Phys J C 75(2):61, 2015), using a hybrid on-shell-[Formula: see text] scheme, with apparently different results. We show that the differences can be traced back to a different renormalization of the top-quark mass, and that the claim in Ref. Degrassi et al. (Eur Phys J C 75(2):61, 2015) of an inconsistency in Ref. Borowka et al. (Eur Phys J C 74(8):2994, 2014) is incorrect. We furthermore compare consistently the results for [Formula: see text] obtained with the top-quark mass renormalized on-shell and [Formula: see text]. The latter calculation has been added to the FeynHiggs package and can be used to estimate missing higher-order corrections beyond the two-loop level.

Diffusion chamber system for testing of collagen-based cell migration barriers for separation of ligament enthesis zones in tissue-engineered ACL constructs

A temporary barrier separating scaffold zones seeded with different cell types prevents faster growing cells from overgrowing co-cultured cells within the same construct. This barrier should allow sufficient nutrient diffusion through the scaffold. The aim of this study was to test the effect of two variants of collagen-based barriers on macromolecule diffusion, viability, and the spreading efficiency of primary ligament cells on embroidered scaffolds. Two collagen barriers, a thread consisting of a twisted film tape and a sponge, were integrated into embroidered poly(lactic-co-caprolactone) and polypropylene scaffolds, which had the dimension of lapine anterior cruciate ligaments (ACL). A diffusion chamber system was designed and established to monitor nutrient diffusion using fluorescein isothiocyanate-labeled dextran of different molecular weights (20, 40, 150, 500 kDa). Vitality of primary lapine ACL cells was tested at days 7 and 14 after seeding using fluorescein diacetate and ethidium bromide staining. Cell spreading on the scaffold surface was measured using histomorphometry. Nuclei staining of the cross-sectioned scaffolds revealed the penetration of ligament cells through both barrier types. The diffusion chamber was suitable to characterize the diffusivity of dextran molecules through embroidered scaffolds with or without integrated collagen barriers. The diffusion coefficients were generally significantly lower in scaffolds with barriers compared to those without barriers. No significant differences between diffusion coefficients of both barrier types were detected. Both barriers were cyto-compatible and prevented most of the ACL cells from crossing the barrier, whereby the collagen thread was easier to handle and allowed a higher rate of cell spreading.

In vitro characterization of self-assembled anterior cruciate ligament cell spheroids for ligament tissue engineering

Tissue engineering of an anterior cruciate ligament (ACL) implant with functional enthesis requires site-directed seeding of different cell types on the same scaffold. Therefore, we studied the suitability of self-assembled three-dimensional spheroids generated by lapine ACL ligament fibroblasts for directed scaffold colonization. The spheroids were characterized in vitro during 14 days in static and 7 days in dynamic culture. Size maintenance of self-assembled spheroids, the vitality, the morphology and the expression pattern of the cells were monitored. Additionally, we analyzed the total sulfated glycosaminoglycan, collagen contents and the expression of the ligament components type I collagen, decorin and tenascin C on protein and for COL1A1, DCN and TNMD on gene level in the spheroids. Subsequently, the cell colonization of polylactide-co-caprolactone [P(LA-CL)] and polydioxanone (PDS) polymer scaffolds was assessed in response to a directed, spheroid-based seeding technique. ACL cells were able to self-assemble spheroids and survive over 14 days. The spheroids decreased in size but not in cellularity depending on the culture time and maintained or even increased their differentiation state. The area of P[LA-CL] scaffolds, colonized after 14 days by the cells of one spheroid, was in average 4.57 ± 2.3 mm(2). Scaffolds consisting of the polymer P[LA-CL] were more suitable for colonization by spheroids than PDS embroideries. We conclude that ACL cell spheroids are suitable as site-directed seeding strategy for scaffolds in ACL tissue engineering approaches and recommend the use of freshly assembled spheroids for scaffold colonization, due to their balanced proliferation and differentiation.

Survival after neoadjuvant chemotherapy with or without bevacizumab or everolimus for HER2-negative primary breast cancer (GBG 44-GeparQuinto)†

BACKGROUND

The GeparQuinto study showed that adding bevacizumab to 24 weeks of anthracycline-taxane-based neoadjuvant chemotherapy increases pathological complete response (pCR) rates overall and specifically in patients with triple-negative breast cancer (TNBC). No difference in pCR rate was observed for adding everolimus to paclitaxel in nonearly responding patients. Here, we present disease-free (DFS) and overall survival (OS) analyses.

PATIENTS AND METHODS

Patients (n = 1948) with HER2-negative tumors of a median tumor size of 4 cm were randomly assigned to neoadjuvant treatment with epirubicin/cyclophosphamide followed by docetaxel (EC-T) with or without eight infusions of bevacizumab every 3 weeks before surgery. Patients without clinical response to EC ± Bevacizumab were randomized to 12 weekly cycles paclitaxel with or without everolimus 5 mg/day. To detect a hazard ratio (HR) of 0.75 (α = 0.05, β = 0.8) 379 events had to be observed in the bevacizumab arms.

RESULTS

With a median follow-up of 3.8 years, 3-year DFS was 80.8% and 3-year OS was 89.7%. Outcome was not different for patients receiving bevacizumab (HR 1.03; P = 0.784 for DFS and HR 0.974; P = 0.842 for OS) compared with patients receiving chemotherapy alone. Patients with TNBC similarly showed no improvement in DFS (HR = 0.99; P = 0.941) and OS (HR = 1.02; P = 0.891) when treated with bevacizumab. No other predefined subgroup (HR+/HER2-; locally advanced (cT4 or cN3) or not; cT1-3 or cT4; pCR or not) showed a significant benefit. No difference in DFS (HR 0.997; P = 0.987) and OS (HR 1.11; P = 0.658) was observed for nonearly responding patients receiving paclitaxel with or without everolimus overall as well as in subgroups.

CONCLUSIONS

Long-term results, in opposite to the results of pCR, do not support the neoadjuvant use of bevacizumab in addition to an anthracycline-taxane-based chemotherapy or everolimus in addition to paclitaxel for nonearly responding patients.

CLINICAL TRIAL NUMBER

NCT 00567554, www.clinicaltrials.gov.

Triplett-Lebensdauern von Diphenylpolyenen und deuterierten Stilbenen in eingefrorener Lösung bei 77°K / Triplet Lifetime of Diphenylpolyenes and deuterated Stilbenes in frozen solution at 77°K

The lowest triplet states of diphenylpolyenes and of deuterated stilbenes were observed by means of photoflash asportion spectroscopy. The diphenylpolyenes do not show phosphorescence. The triplet lifetime is strongly dependent on triplet energy. This is consistent with the known influence of Franck-Condon factors. The triplet lifetime of partially deuterated stilbenes depends on the number and the position of the deuterium atoms. The effect of olefinic monodeuteration on the non-radiative process is approximately 16 times larger than that of deuteration at an aromatic position. The observations can be explained in terms of isotope effects on vibronic spin-orbit coupling.

Die Lösungsmittelabhängigkeit der thermischen cis-trans-Isomerisierung von N-Benzylidenanilinen mit Donator/Akzeptor-Substituenten

Thermal cis →-trans isomerization of eight N-benzylideneanilines with donor and/or acceptor substituents in the para, para'-positions was studied in different solvents by observing the rapid relaxation to the thermodynamic stable trans isomer following flash photolysis. With the push-pull effect of the substituents in the direction of the N-aryl group the rate constant at 25°C is by three powers of 10 faster compared to the N–benzylideneaniline with opposite arrangement of substituents. The rate constants are independent of the nature of the substituents in the para-position of the benzylidene group. The rate constants of N-(4-nitrobenzylidene)-p-anisidine are linear functions of the solvent polarity scale based on solvatochromic shifts (Kosowers Z-value or Dimroths ET-value). With increasing push-pull effect of the substituents in the direction of the N-aryl group the rate constants do no longer depend on the polarity of the solvent. The observed solvent effects on the rates and the activation energies for thermal cis→ trans isomerization suggest that the transition state of the reaction is less polar than the ground state of the sterically hindered cis-N-benzylideneaniline, thus favouring an inversion mechanism to become operative with respect to the N-benzylideneanilines.

Insektenhäutungshormone und ihre Wirkungsweise

25-Desoxyecdysteron und Ecdysteron werden im Fettkörper von Larven der Schmeißfliege Calliphora erythrocephala umgewandelt in Glykoside. Aus enzymatischen und chemischen Untersuchungen schließen wir, daß 3β- (α-Glucopyranosido) -Derivate der Hormone gebildet werden. Bereits 30 Min. nach Injektion von 3 Calliphora-Einheiten/Larve sind 85% des Hormons in das Glykosid umgewandelt. Im Erfolgsorgan Epidermis findet weder eine Glykosid-Synthese statt noch wird das Glykosid in stärkerem Ausmaß von der Epidermis aufgenommen. Die Glykosidbildung erfolgt durch eine Uridindiphosphalglucose: Ecdysteron-Transglucosylasc.

Photoelectron Spectroscopy of Substituted N-Benzylideneanilines

The electronic structure and conformation in the gas phase of N-benzylideneaniline, its para-nitro and -methoxy as well as the ring perfluorinated derivatives were investigated by photoelectron (PE) spectroscopy and semiempirical molecular orbital (HMO) calculations. The π-ionizations were assigned and it is shown that these compounds in the gas phase are in a nonplanar conformation.

Hierarchically structured nerve guidance channels based on poly-3-hydroxybutyrate enhance oriented axonal outgrowth

Traumatic peripheral nerve lesions can cause local anesthesia, paralysis and loss of autonomic control. Reconstruction using engineered nerve guidance conduits (NGCs) is rarely successful due to the sub-optimal characteristics of the conduits. To address the demands of clinical practice, we developed a hierarchically structured NGC from slowly resorbing poly(3-hydroxybutyric acid) (P3HB). The NGC consists of a permeable single-lumen tube and melt-spun fibrillar lumen fillers. Permeable tubes were constructed from P3HB/poly(ɛ-caprolactone) (PCL) blends or poly(3-hydroxybutyric acid-co-4-hydroxybutyric acid) (P(3HB-co-4HB)). Polyvinylpyrrolidone was used as a porogen in solvent-free thermoplastic processing, followed by selective polymer leaching. All tested material compositions showed hydrolytic degradation after 16weeks in phosphate buffered saline, whereas P3HB/PCL tubes maintained mechanical strength compared to (P(3HB-co-4HB)). The porous scaffolds allowed diffusion of large molecules (∼70kDa). In vitro studies demonstrated that mouse fibroblasts survived and proliferated inside closed porous tubes. An in vitro model of axonal regeneration using dorsal root ganglia and sympathetic cervical ganglia demonstrated that the NGCs successfully supported neuron survival and neurite outgrowth. The introduction of fibrillar lumen fillers promoted oriented neurite growth and coating with extracellular matrix proteins further increased ganglia attachment and cell migration. In this study we show that P3HB-based NGCs scaffolds have potential in long gap peripheral nerve repair strategies.

Abstract P3-12-09: The prevalence and quantity of circulating tumor cells (CTCs) after adjuvant chemotherapy with and without anthracyclines in patients with HER2-negative early breast cancer (EBC)

Background: The use of anthracycline based chemotherapy in early breast cancer (EBC) patients has been well established. However, adverse effects like cardiotoxicity and efficacy in certain subgroups continue to be subjects of discussion. Based on data suggesting a limited benefit of anthracyclines in HER2-negative patients, the German SUCCESS C study randomly assigned patients with EBC to be treated with either anthracycline-containing or anthracycline-free chemotherapy. Since the prognostic value of CTCs in EBC has already been demonstrated in several trials, we compared the prevalence of CTCs after the completion of chemotherapy between both treatment arms.

Methods: The SUCCESS C trial was a randomized, open-label, Phase III study comparing disease free survival (DFS) in patients with HER2-negative EBC. Treatments were either 3 cycles epirubicin, 5-fluorouracil and cyclophosphamide followed by 3 cycles of docetaxel (FEC–DOC), or 6 cycles of an anthracycline-free regimen with docetaxel and cyclophosphamide (DOC-C). The CTC status at chemotherapy cycle 6 was prospectively evaluated using the FDA-approved CellSearch System (Veridex, USA).

Results: Data on CTC status after chemotherapy are available for 1757 patients. Overall, CTCs were found in 220 (12.5%) patients (median 1, range 1 – 18 CTCs). One CTC was detected in 123 (55.9%), two CTCs in 53 (24.1%), three to five CTCs in 37 (16.8%), and more than five CTCs in 7 (3.2%) of these patients. Univariate analyses revealed that CTC prevalence was not significantly associated with tumor size (pT1, pT2, pT3, pT4), nodal stage (pN0, pN1, pN2, pN3), grading (G1, G2, G3), histological type (invasive ductal, invasive lobular, other), estrogen-receptor status, or progesterone-receptor status (Chi-square tests, all p &gt; 0.1). There was no significant difference with respect to the prevalence of CTCs after chemotherapy between the two treatment arms (Chi-square test, p = 0.23), as CTCs were detected in 11.6% (103 out of 889) of patients treated with the anthracycline-containing chemotherapy regimen and in 13.5% (117 out of 868) of patients treated with the anthracycline-free chemotherapy regimen. In addition, there was no significant difference between the two treatment arms with regard to the number of CTCs detected after chemotherapy in CTC-positive patients (FEC-DOC: median = 1, range 1 – 18; DOC-C: median = 1, range 1 – 8; Mann-Whitney U test, p = 0.30).

Conclusions: The comparable prevalence and number of CTCs after the completion of chemotherapy may indicate that anthracycline-free chemotherapy is not inferior to anthracycline-containing chemotherapy in this study. This however, has to be confirmed by survival analyses, which will be available in 2014.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-12-09.

INFLUENCE OF FIBER TYPE AND COATING ON THE COMPOSITE PROPERTIES OF EPDM COMPOUNDS REINFORCED WITH SHORT ARAMID FIBERS

There is a renewed interest in the application of short aramid fibers in elastomers because of the considerable improvement in mechanical and dynamic properties of the corresponding rubber composites. Possible applications of short aramid fiber–reinforced elastomers are tires, dynamically loaded rubber seals, diaphragms, engine mounts, transmission belts, conveyer belts, and hoses. Our studies are related to the investigation of dispersion, length distribution, and the fiber–matrix interaction of two types of short aramid fibers, standard coated and resorcinol formaldehyde latex (RFL) coated, in ethylene–propylene–diene rubber (EPDM). Because the detection of the polymer fiber morphology in rubber compounds is hampered in the presence of carbon black, which is typically used in industrial elastomer compounds, fiber length, fiber length distribution, and dispersion are investigated in corresponding carbon black–free model compounds. Optical methods, scanning electron microscopy, and tensile testing are employed to explore the short aramid fiber–reinforced elastomer composites. The effects of morphology and fiber–matrix interaction on the mechanical properties of composites are discussed. Regarding fiber type, it is shown that co-poly-(paraphenylene/3,4′-oxydiphenylene terephthalamide) (PP/ODPTA) fibers end up with a higher final length than does poly(para-phenylene terephtalamide) (PPTA), which results in considerably higher mechanical properties of corresponding rubber compounds. For each fiber type, the higher final length as a result of RFL coating and the interaction with the rubber matrix are the key factors that overcome even the negative effect of poorer dispersion of RFL-coated fibers. The differences between the short aramid fibers and aramid cords regarding the RFL coating are also discussed.

A numerical study on deformation of Newtonian droplets through converging cylindrical dies

In this work, the dynamic deformation of a viscose Newtonian droplet passing through cylindrical converging dies has been studied. The changes in the interfacial area between two immiscible Newtonian fluids have been considered as a variable representing the time-dependent deformation of a circular droplet along converging dies. To do so, a surface tracking method has been incorporated into a finite element code, developed by the authors, which quantifies the deformation of the droplet through the converging path, and where the surface area of the deformed drop has been consequently chosen as a criterion for a two-phase interface. In this study, it has been revealed that by changing both rheological and geometrical parameters it is possible to manage the value of interface area between two phases. Ultimately, a unique curve is developed for each droplet to primary phase viscosity ratio which can correlate drop deformation with geometrical parameters.

Precise QCD predictions for the production of a photon pair in association with two jets

We compute the cross section for the production of a high-mass photon pair in association with two hadronic jets to next-to-leading order in quantum chromodynamics. Our results allow us for the first time to reliably predict the absolute normalization of this process and demonstrate that the shape of important kinematical distributions is modified by higher-order effects. The perturbative corrections will be an important ingredient in precision studies of Higgs boson properties from its production in association with two jets.

The Effect of Silane Treated Hybrid Filler on the Mechanical and Thermal Performance of Carboxylated Nitrile Butadiene Rubber (XNBR) Composites

Carboxylated Nitrile Butadiene Rubber (XNBR) was reinforced with untreated and silane treated hybrid filler. The hybrid filler was composed of organic layered nanosilicates (NLS) and agro polymer based olive husk powder (OHP). The fabricated composites were inspected with regard to their mechanical and thermal properties. It was found that the silane treated hybrid filler was able to improve the tensile strength at break and the tensile modulus as compared to the control. The overall degree of interaction between the matrix and both the untreated and treated hybrid filler was improved. This was evidenced by the increased degree of curing which is the torque difference (τmax–τmin) derived from the moving die rheometer (MDR) and the decreased swelling index data. Dynamic mechanical analysis (DMA) revealed that the apparent was the highest in case of the silane treated hybrid filler. The thermogravimetric analysis (TGA) revealed that the thermal stability of the composites improved with the incorporation of the hybrid filler. The attenuated total reflectance (ATR-IR) revealed that dipole-dipole interactions between the various reactive functional groups namely the carboxylic of the XNBR, the hydroxyl group of the agro-polymer and the silanol of the silane agent occurred during the fabrication stage of the composites. Scanning electron microscopy (SEM) showed that the fracture surface of the samples differ after the incorporation of the treated hybrid filler.

Influence of the Cross-sectional Geometry on Wettability and Cleanability of Polyester Woven Fabrics

Filament cross-sections used in textiles and composites are becoming more and more complex. The type of cross-sectional shape impacts filament properties and are therefore, yarn and fabric characteristics. In this paper, the influence of different filament cross-section geometry on fibre properties as well as on fabric surface characteristics was studied. PET (polyethylene terephthalate) filament yarns made from two different cross-sectional shaped filaments, round and cruciform, were manufactured by the melt spinning process. Polyester fabrics were manufactured in a needle band weave machine from these two types of filament yarns. Topographic characteristics of polyester fabrics manufactured were determined by an imaging instrument for optical roughness analysis based on the principle of chromatic aberration. Differences between soiling behaviour, cleanability and wettability of the fabrics were revealed and discussed.

The Influence of Different Ether Carboxylic Acids on Polyester Fibre Friction

The influence of different surface active ether carboxylic acids as spin finishes on polyester fibre friction has been studied. The fibre friction was indirectly assessed through measurements of yarn tensile forces during the melt-spinning process. After manufacturing, the friction of fibre against steel was evaluated using the method of inclined plane. Results for the static fibre-steel friction coefficient obtained are in good agreement with the yarn tensile force data. The influence of different finishing agents as lubricants on the fibre friction was revealed.