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Chromophore relaxation is still one of the major problems with NLO polymers. One strategy to overcome this problem is the synthesis of polymers with high glass transition temperatures. We have prepared a number of polymers by copolymerization of NLO-active methacrylates with the bulky adamantyl methacrylate. This leads to polymers with glass transition temperatures up to 190 °C. The synthesis and properties of these polymers are reported in detail. The polymers show a good long term stability of the electrooptic coefficient (r33) at elevated temperatures. So polymer 3c with a bisazo chromophore shows only a 25 % EO-coefficient decay after one month at 120 °C.

A number of novel nonlinear optically (NLO) active polymethacrylates were prepared from the NLO active methacrylates 2a–d with azobenzene side groups and the bulky comonomer 1-adamantyl methacrylate. The polymers exhibit unusually high glass transition temperatures between 160°C and 190°C. The copolymerization parameters of the monomer pair 1-adamantyl methacrylate (1)/Disperse red methacrylate 2b (r1 = 1,1 ± 0,2, r2 = 0,8 ± 0,2) show that the two monomers are incorporated almost statistically into the polymer chain. Polymers 3a–d are soluble in common organic solvents and excellent films can be obtained by spin coating. After poling in an electric field of 120 V/μm polymer 3b shows a large electrooptic (EO) coefficient (r33) of 25 pm/V at 633 nm. Within two weeks, only a negligible decay of 7% of the EO coefficient was observed at room temperature. On-line monitoring of the second harmonic generation (SHG) at 100°C showed a fast initial drop (10%) of the SHG signal and subsequently a slow decay of 20% within 10 h. Afterwards, the signal remained almost constant for further 5 h at 100°C. The novel polymers can thus be considered as easy processible NLO materials with a high thermal stability of the chromophore orientation obtained by poling.

Chromosome 11 abnormalities are found in many hematological malignancies. In acute myeloid leukemia (AML), a proto-oncogene MLL (11q23.3) is frequently altered. However, rearrangements involving other regions of chromosome 11 have been reported. Therefore, we have characterized the chromosome 11 breakpoints and common deleted and amplified areas in the bone marrow or peripheral blood cells of newly diagnosed patients with AML. Using molecular-cytogenetic methods (multicolor fluorescence in situ hybridization (mFISH), multicolor banding (mBAND), microarrays, and FISH with bacterial artificial chromosome (BAC) probes, chromosome 11 abnormalities were delineated in 54 out of 300 (18%) newly diagnosed AML patients. At least 36 different chromosome 11 breakpoints were identified; two were recurrent (11p15.4 in the NUP98 gene and 11q23.3 in the MLL gene), and three were possibly nonrandom: 11p13 (ch11:29.31-31.80 Mb), 11p12 (ch11:36.75-37.49 Mb) and 11q13.2 (68.31-68.52 Mb). One new MLL gene rearrangement is also described. No commonly deleted region of chromosome 11 was identified. However, some regions were affected more often: 11pter-11p15.5 (n = 4; ch11:0-3.52 Mb), 11p14.1-11p13 (n = 4; ch11:28.00-31.00 Mb) and 11p13 (n = 4; ch11:31.00-31.50 Mb). One commonly duplicated (3 copies) region was identified in chromosomal band 11q23.3-11q24 (n = 9; ch11:118.35-125.00 Mb). In all eight cases of 11q amplification (3 copies), only the 5' part of the MLL gene was affected. This study highlights several chromosome 11 loci that might be important for the leukemogeneic process in AML.

The quality of medical plants used for the production of galenics or pharmacologically useful compounds is usually assessed by the content of biologically active compounds. Because most of these plants are grown in fields, this study focused on stimulation of active compounds by in vivo elicitation. Foliar application of elicitors on the immunostimulating medical plant purple coneflower ( Echinacea purpurea L. Moench.) grown on soil was used to increase the content of biologically active phenolics. Natural plant stress mediators and their derivatives (acetylsalicylic acid, salicylic acid, and methyl salicylate) as well as newly introduced biocompatible metal elicitor [titanium(IV) ascorbate] were chosen as active components of foliar sprays. A tremendous increase of phenolics (up to 10 times compared to control) and stimulation of the biomass yield were achieved. Tuning of organ specificity by modulation of the concentration of elicitor was also observed. This methodology represents a convenient alternative to cell suspension or hydroponic cultures being applicable in wide agricultural practice.

We present a nondestructive experimental technique for the determination of the lateral distribution of the polar order in second-order nonlinear optical thin films. The sample, which consists of a poled polymer film is scanned through the focus of an infrared laser beam in a second-harmonic generation setup and the second-harmonic intensity is monitored stepwise. In combination with a conventional electro-optic (EO) characterization it is possible to create an EO-coefficient map of the sample. The resolution of this mapping technique can be significantly increased by using high numerical aperture microscope optics for the illumination of the poled polymer. This method, for instance, allows the evaluation of poling inhomogeneities due to high-field poling and field distortions at the edges of poling electrodes.

We present an experimental technique for nondestructive measurement of the glass transition temperature (Tg) of thin nonlinear optical (NLO) polymer films by attenuated total reflection spectroscopy. At Tg the thermal expansion coefficient and temperature dependence of the refractive index ∂n/∂T change discontinuously. This change can be detected with high sensitivity by recording thickness and refractive index of a polymer waveguide coated on a glass/gold substrate as a function of temperature. Measurements were made on various high Tg NLO polymers (Tg up to 170 °C). The resulting Tg values are compared with those determined by differential scanning calorimetry of the bulk material.

The chemical and physical properties of photobleached nonlinear optical (NLO)‐polymethacrylates were studied in order to investigate photobleaching mechanisms. We have shown by three key measurement techniques (infrared‐spectroscopy, mass spectrometry, and gel permeation chromatography) that the predominant bleaching process is an irreversible decomposition of the NLO moieties accompanied by a broadening of the polymer molecular weight distribution. The quantum yield of the chromophore degradation determined by the evaluation of the bleaching kinetics fit is in agreement with typical data from comparable chromophores. It was found that bleaching causes an increase in surface roughness of NLO‐polymer films, causing an increase in waveguide loss. Smoothing of the film surface by an annealing step leads to a lowering of bleaching induced waveguide loss.

Deep UV application of optical fibers has been restricted due to the strong photodegradation in silica fibers transmitting deep UV light. We have developed an improved all silica preform for the production of multimode fibers with drastically improved resistance to UV-light. Two key experiments have been performed in order to characterize the solarization behavior of such fibers: (1) ArF-excimer laser and deuterium lamp photodegradation spectroscopy enables the in situ observation of defect center creation. (2) Long time photodegradation excimer laser experiments (ArF and KrF) are a good tool to predict the fiber's lifetime for applications with such lasers. Compared to standard high OH all silica fibers the optimized fibers show an exceptionally low creation of E'-centers (215 nm). Hydrogen doping of such fibers further increases the UV-resistance: Even after prolonged excimer laser irradiation (ArF: 20 X 10 6 pulses, 5 mJ/cm 2 , 400 Hz; KrF: 20 X 10 6 pulses, 50 mJ/cm 2 , 500 Hz) these fibers maintained their very high initial transmission, neither E'-center nor NBOH-center (265 nm) absorption could be observed.

Optical fibers with broadband transmission from the UV through the IR have not been available because the silica core material either has OH absorption bands in the IR or UV absorption due to intrinsic structural defects or chlorine. We have developed a new silica core material which can be fabricated into an optical fiber with very good transmission characteristics from 350 nm to 2000 nm. The transmission performance is stable with time because the fiber is not doped with hydrogen.

We present a novel nondestructive experimental technique for the determination of the lateral distribution of the polar order in second order nonlinear optical (NLO) thin films. The sample, which consists of a poled polymer film, is scanned through the focus of an infrared laser beam in a second harmonic generation (SHG) setup and the second harmonic intensity is monitored stepwise. In combination with a conventional electrooptic (EO) characterization it is possible to create an EO-coefficient map of the sample. The resolution of this mapping technique can be significantly increased by using high numerical aperture (NA) microscope optics for the illumination of the poled polymer. This method, for instance, allows the evaluation ofpoling inhomogeneities due to high field poling and field distortions at the edges ofpoling electrodes.

The development of polymeric devices for integrated optical applications has recently received much attention [1]. The thermodynamic properties of the waveguiding materials are of vital interest in this field. In particular the fabrication of active components based on poled nonlinear chromophore functionalized polymers requires knowledge of the materials’ glass transition temperature T g , since the relaxation of noncentrosymmetric orientational order is strongly related to the glass transition.

A new copolymer system with high, but still variable glass-transition temperatures was synthesized. The fixation of various NLO-chromophores is performed after the radical is performed after the radical copolymerization by a polymer analogous reaction. This was accomplished by copolymerizing various N-substituted maleimides with methylvinyl- or vinylisocyanate, so that a polymer with a 1:1 composition of the two monomers and reactive isocynate side-groups is obtained. With different substituents attached to the imide-ring, Tg can be adjusted between 100 and 200 degrees C. Two effects of the substituent at the imide-nitrogen are observed. Bulky gorups reduce the mobility of the chain and lead to high Tg values. A similar tendency is found for smaller less flexible substituents. In this case the intermolecular forces by hydrogen-bonding (urethanes) contibute ot the effects for high Tg's. A variety of different NLO-chromopores can be fixed on the polymer backbone by reaction of a hydroxyalkyl-spacer with the isocyanates, so that a urethane linkage between the chromophore and the polymer is formed. Based on the experience obtained with this first class of NLO-materials, new functionalized polymers were prepared. In order to further increase the Tg-values, while keeping a good processability (solubility), chemical modifications of the spin-coated polymer were prepared. In order to further increase the Tg-values, while keeping a good processablility (solubility), chemical modifications of the spin-coated polymer were performed. Monomers functionalized with tertiary butyl groups (esters or carbonates) allow it, to split off isobutene from the final (and processed) polymer, thereby reducing its solubility and increasing its Tg-value.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Photobleaching experiments on thin films of azo chromophore functionalized methacrylates were carried out to investigate bleaching kinetics and its underlying mechanisms. The polymer film's spatial index variation was measured and compared with a theoretical model of bleaching dynamics. From IR-spectroscopy and from GPC measurements it was found, that bleaching causes a destruction of the chromophore and a broadening of the polymer molecular weight distribution. The generated low molecular weight fractions from both polymer and chromophore photodecay evaporate during annealing above Tg, resulting in a reduction of the film's thickness. Surface roughness increases during photobleaching, causing an increase in waveguide loss. Film surface can be smoothed completely by annealing, thus lowering the optical loss induced by bleaching.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Chromophore relaxation is still one of the major problems of NLO polymers. Two strategies have been developed to overcome this problem. One of them is crosslinking after poling. We synthesized new polymers with methylfuryl acryloyl side groups. Upon irradiation with UV- light, they undergo a (2 + 2) cycloaddition which leads to a highly crosslinked material. Compared to cinnamoyl gorups frequently used in such polymers, the absorption of the novel crosslinker is shifted to longer wavelengths. This allows to use a cutoff filter during irradiation and therewith minimizes chromophore decomposition. The second way to suppress chromophore relaxation is the use of polymers with high glass transition temperatuers. We have prepared a number of polymers by copolymerization of NLO-active methacrylates with the bulky adamantyl methacrylate. This leads to polymers with glass transition temperatures up to 190 degrees C. The synthesis and properties of these polymers are reported in detail. The polymers shown a good long term stability of the electro-optic coefficient (r33) with its relaxation approximately following a KWW-function.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Four high T g side chain polymers have been investigated based on polyimide and acrylate backbones functionalized with DR1 and heterocyclic thiophene chromophores. UV-VIS studies revealed chromophore stability up to 210 degree(s)C. Maximum poling efficiency was found approximately 15 K above T g . From dielectric relaxation studies and from poling dynamics it is obvious that chromophore reorientation follows an Arrhenius law at temperatures well above T g leading into a WLF-behavior in the vicinity of T g . Relaxation of the EO-coefficient could be interpreted in terms of a KWW function. The average relaxation times strongly deviate from the WLF-function at temperatures well below T g and can be described with an Arrhenius law. Activation energies here are significantly smaller than those in the high temperature limit above T g , indicating that the chromophore dipoles are incompletely coupled to the polymer (alpha) process. Very good stability was observed for the polyimide P3 with average relaxation times of 10 4 years at 50 degree(s)C and 4 months at 120 degree(s)C. EO coefficients of up to 12 pm/V at 1541 nm were realized using a poling field strength of 1 MV/cm. EO-coefficient at constant poling field was found to be approximately linearly dependent on chromophore content. Channeled waveguides were fabricated by selective reactive ion etching with small losses of 1 dB/cm at 1318 nm. However, loss varies strongly between 1 dB/cm and 3 dB/cm depending on film quality.

Abstract 4905 Modern molecular diagnostic techniques allow the detection of minimal residual disease (MRD) in hematological malignancies with high sensitivity, allowing patient-specific assays of MRD levels over the course of treatment. One challenge for these techniques is finding appropriate MRD marker targets. For instance, PCR-based MRD analysis requires unique sequence-specific information for the malignant clone of interest. In many acute leukemias, such detailed information is lacking, either because no abnormality is detected (e.g. in 40–50% of adult Acute myeloid leukemia-AML), or the resolution of cytogenetic methods is too low to precisely define newly-found abnormalities. We have used multicolor-FISH (mFISH) to perform karyotyping of 141 patients. Using this approach we have identified chromosomal abnormalities in about 35% of analyzed cases. The aberrations found involved the recurrent aberrations t(15;17), t(8;21), inv(16), t(9;22),−5q, −7, +8 but also an array of unique abnormalities, such as der(15)t(5;15)(q15;q24), t(6;12)(p22;q13), and der(17)t(12;17)(q14;pter), which may serve as possible targets for molecular MRD follow-up. To further characterize such targets, we seek to bridge the gap from cytogenetic resolution down to higher-resolution molecular techniques. For this, we first employ the mBAND technique, followed by multicolor FISH using DNA probes with known cytogenetic location. These probes are drawn from the Human Minimal Genomic Clone Set (Version 1.0, Source Bioscience LifeSciences) of over 25,000 bacterial artificial chromosome (BAC) clones with human DNA inserts. These are tiling clones covering almost 100% of the genome, and therefore allow us to develop FISH probes to regions containing almost any conceivable target breakpoint. Starting with breakpoint information from mFISH/mBAND, we perform consecutive multi-color/multi-BAC hybridizations around the region of interest, looking for breakpoint-spanning probes. Using this system, we are able to move from a resolution of around 2 Mbp (the limit of mBAND) to the resolution of individual BAC clones (average 150 kbp) in three hybridizations. To achieve further resolution, long-range PCR products are designed within the region defined by breakpoint-spanning BACs, with labeling and FISH-mapping of these probes. At present, we are starting to perform these hybridizations on stretched DNA (fiber-FISH or combed DNA), where one micrometer of a stretched DNA molecule represents about 2000 base pairs, allowing visualization of probe distance and spacing, and even higher-resolution breakpoint analysis. Chromosome microdissection followed by high-throughput sequencing (Roche GS Junior) is also being pursued to identify novel breakpoints by rapidly sequencing large chromosomal regions on both sides of a translocation. The final goal is to map genomic abnormalities to a resolution amenable to long-range PCR, yielding specific targets for MRD detection, and allowing clone-specific Real-Time PCR assays for sensitive and specific monitoring of MRD in hematooncological patients. Disclosures: Smolej: GlaxoSmithKline: Honoraria, Membership on an entity's Board of Directors or advisory committees, Travel Grants; Roche: Honoraria, Travel Grants; Genzyme: Honoraria, Travel Grants.

Human parainfluenza viruses (HPIVs) are uncommon, yet high-risk pathogens after hematopoietic stem cell transplant (HCT). We evaluated 5178 pediatric and adult patients undergoing HCT between 1974 and 2010 to determine the incidence, risk factors, response to treatment, and outcome of HPIV infection as well as any change in frequency or character of HPIV infection over time. HPIV was identified in 173 patients (3.3%); type 3 was most common (66%). HPIV involved upper respiratory tract infection (URTI; 57%), lower respiratory tract infection (LRTI; 9%), and both areas of the respiratory tract (34%), at a median of 62 days after transplantation. In more recent years, HPIV has occurred later after HCT, whereas the proportion with nosocomial infection and mortality decreased. Over the last decade, HPIV was more common in older patients and in those receiving reduced intensity conditioning (RIC). RIC was a significant risk factor for later (beyond day +30). HPIV infections, and this association was strongest in patients with URTI. HCT using a matched unrelated donor (MURD), mismatched related donor (MMRD), age 10 to 19 years, and graft-versus-host disease (GVHD) were all risk factors for HPIV infections. LRTI, early (

Abstract 2526 Many studies on childhood and adult leukemias have demonstrated that thorough molecular analysis at the time of diagnosis and minimal residual disease (MRD) follow-up are significantly related to the prognosis, and overall- and event-free survival, of patients with acute leukemias. In acute myeloid leukemia (AML), such complex molecular diagnostics and subsequent MRD evaluations are important factors for proper stratification, disease prognosis, assessment of the treatment response, optimal dosage and duration of chemotherapy, and estimation of the optimal timing for hematopoietic stem cell transplantation. Upon diagnosis, the bone marrow samples of AML patients are routinely screened for an array of recurrent chromosomal abnormalities, including chromosomal translocations (e.g. PML/RARa, AML1/ETO, CBFb/MYH11, MLL fusions, BCR/ABL) or leukemia-associated genetic mutations (e.g. mutations in genes NPM1, WT1, FLT3, MLL or CEBPa). Given the fact that laboratories often deal with a limited amount of material sampled for molecular investigations, and the number of possible genomic aberrations and molecular targets is high, it is desirable to implement in routine practice a flexible tool that allows testing for as many genetic abnormalities as possible, while reducing the amount of biological material required for analyses to a minimum. In our laboratory, we have developed a multiplex Real-Time PCR technique allowing us to examine over 75 recurrent chromosomal aberrations in only 10 multiplex PCR reactions (Table 1). The methodology makes use of a set of fluorescently labeled TaqMan hybridization probes, labeled by 5 different fluorophores. Using this methodology we are able to assess the presence of both rare as well as recurrent chromosomal translocations/aberrations in one setting, from a limited amount of starting material. This approach is not only extremely beneficial for the leukemic patient - which is always the primary goal - but also for the overall budgeting of routine molecular screening of diagnostic AML samples.Table 1:List of the AML-associated chromosomal abnormalities included in the 5-Color Multiplex Real-Time PCR system. The multiplexing of individual molecular targets is indicated by the individual PCR tubes (A to J) used in the diagnostic screening of AML in our laboratory. Importantly, a clone-specific chromosomal abnormality found at the time of diagnosis using our 5-Color Multiplex Real-Time PCR system allows us to molecularly follow-up the MRD level with a high sensitivity of 10e-4 to 10e-6, as assessed by serial dilutions of cloned standards harboring the individual aberrant genetic targets. This complex molecular approach considerably helps hematooncologists in clinical decision making and the adjustment and modulation of the treatment of AML patients in respect to their individual needs and their individual disease course. Since 2005 we have molecularly investigated 398 adult AML cases. Using the 5-Color Multiplex Real-Time PCR technique and mutational screening we were able to identify a clone-specific abnormality in 45.2% of cases. The clone-specific genetic markers were then used as specific molecular targets for a clone-specific MRD follow-up. Although in approximately 50% of AML patients we are still not able to identify any clone-specific abnormality to be used for either stratification (recurrent abnormalities) or molecular MRD follow-up (both recurrent and unique/rare abnormalities) of these leukemic patients, our 5-Color Multiplex Real-Time PCR system, being an open platform, enables us to flexibly implement any newly identified chromosomal aberrations to the diagnostic portfolio, thus increase the probability of finding a clone-specific molecular marker with all the positive consequences in respect to the management of patients with acute leukemia. Disclosures: Smolej: GlaxoSmithKline: Honoraria, Membership on an entity's Board of Directors or advisory committees, Travel Grants; Roche: Honoraria, Travel Grants; Genzyme: Honoraria, Travel Grants.

Background Breast carcinomas represent a heterogeneous group of tumors diverse in behavior, outcome, and response to therapy. Identification of proteins resembling the tumor biology can improve the diagnosis, prediction, treatment selection, and targeting of therapy. Since the beginning of the post-genomic era, the focus of molecular biology gradually moved from genomes to proteins and proteomes and to their functionality. Proteomics can potentially capture dynamic changes in protein expression integrating both genetic and epigenetic influences. Methods We prepared primary cultures of epithelial cells from 23 breast cancer tissue samples and performed comparative proteomic analysis. Seven patients developed distant metastases within three-year follow-up. These samples were included into a metastase-positive group, the others formed a metastase-negative group. Two-dimensional electrophoretical (2-DE) gels in pH range 4–7 were prepared. Spot densities in 2-DE protein maps were subjected to statistical analyses (R/maanova package) and data-mining analysis (GUHA). For identification of proteins in selected spots, liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed. Results Three protein spots were significantly altered between the metastatic and non-metastatic groups. The correlations were proven at the 0.05 significance level. Nucleophosmin was increased in the group with metastases. The levels of 2,3-trans-enoyl-CoA isomerase and glutathione peroxidase 1 were decreased. Conclusion We have performed an extensive proteomic study of mammary epithelial cells from breast cancer patients. We have found differentially expressed proteins between the samples from metastase-positive and metastase-negative patient groups.