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Polypropylene as one of the world's top commodity polymers is also widely used in the textile industry. However, its non-polar nature and partially crystalline structure significantly complicate the process of industrial coloring of polypropylene. Currently, textiles made of polypropylene or with a significant proportion of polypropylene are dyed under quite harsh conditions, including the use of high pressures and temperatures, which makes this process energy intensive. This research presents a three-step synthesis of coloring agents, capable of adhering onto synthetic polypropylene yarns without harsh energy-consuming conditions. This is possible by encapsulation of organic pigments using trimethoxyphenylsilane, introduction of surface double bonds via modification of the silica shell with trimethoxysilylpropylmethacrylate and final attachment of highly adhesive anchor peptides using thiol-ene chemistry. We demonstrate the applicability of this approach by dyeing polypropylene yarns in a simple process under ambient conditions after giving a step-by-step guide for the synthesis of these new dyeing agents. Finally, the successful dyeing of the yarns is visualized, and its practicability is discussed.

Facile α-H elimination from tetrakis(trimethylsilylmethyl)titanium precursors to give adducts of (alkylidene)bis(alkyl)titanium complexes is induced by light alkali metal amides of the NNNN-type macrocyclic anionic ligand Me3 TACD [(Me3 TACD)H=1,4,7-trimethyl-1,4,7,10-tetraazacyclododecane]. In the crystal, the alkali metal interacts with the carbene carbon atom or with the CH2 group of the trimethylsilymethyl ligand. The nucleophilic character of the carbene carbon atom was shown by the reaction with benzophenone and terminal acetylenes.

Polypropylene as one of the world's top commodity polymers is also widely used in the textile industry. However, its non-polar nature and partially crystalline structure significantly complicate the process of industrial coloring of polypropylene. Currently, textiles made of polypropylene or with a significant proportion of polypropylene are dyed under quite harsh conditions, including the use of high pressures and temperatures, which makes this process energy intensive. This research presents a three-step synthesis of coloring agents, capable of adhering onto synthetic polypropylene yarns without harsh energy-consuming conditions. This is possible by encapsulation of organic pigments using trimethoxyphenylsilane, introduction of surface double bonds via modification of the silica shell with trimethoxysilylpropylmethacrylate and final attachment of highly adhesive anchor peptides using thiolene chemistry. We demonstrate the applicability of this approach by dyeing poly propylene yarns in a simple process under ambient conditions after giving a step-by-step guide for the synthesis of these new dyeing agents. Finally, the successful dyeing of the yarns is visualized, and its practicability is discussed.

A series of light alkali metal organoperoxides [MOOR] (M = Li, Na, K; R = tBu, CMe2Ph) were isolated in mononuclear form, aided by the tetradentate and neutral NNNN-type macrocycle Me4TACD (L; Me4[12]aneN4 = 1,4,7,10-tetramethyl-1,4,7,10-tetraazacyclododecane) and strong hydrogen bonds from additional ROOH molecules. The Na and K compounds are characterized by short OH···O contacts, in the case of the Na derivative as short as 2.41 A.

Alkali metal hydridotriphenylborates [(L1 )M][HBPh3 ] (L1 =Me6 TREN; M=Li, Na, K) chemoselectively catalyze the hydroboration of carbonyls and CO2 , with lithium being the most active system. A new series of complexes [(L2 )M][HBPh3 ] [M=Li (1), Na (2), K (3)] featuring the cyclen-derived macrocyclic polyamine Me4 TACD (L2 ) were synthesized in a "one-pot" fashion and fully characterized including X-ray crystallography. In the crystal, 1-3 exhibit wide variation in metal coordination of the [HBPh3 ]- anion from lithium to potassium. The structures differ from those in [(L1 )M][HBPh3 ]. Effects of coordination of L1 , L2 , and other N- and O-donor multidentate ligands on [Li(HBPh3 )] were used to rationalize the catalytic activity in carbonyl hydroboration.

Triphenylborane (BPh3) abstracted the β-SiH in [(L)M{N(SiHMe2)2}] (L = Me6TREN; M = Li, Na, K) in THF to give the hydridotriphenylborates [(L)M][HBPh3]. Reactions in benzene favored silazide instead of hydride abstraction to give [(L)M][Ph3B–N(SiHMe2)2]. The hydridotriphenylborates [(L)M][HBPh3] catalyzed the chemoselective hydroboration of benzophenone by pinacolborane (HBpin), with the lithium derivative being the most active. The solution structure of [(L)Li][HBPh3] was qualitatively investigated in the context of its superior catalytic activity. Fluxional coordination of L in [(L)Li(THF)]+ in tandem with a THF solvent molecule was revealed by NMR spectroscopy. para-Substituents in [HB(C6H4-p-X)3]− influenced the rate which is apparently determined by the addition of the B–H function to the isolable alkoxy borate intermediate [(L)Li][Ph2CHOBPh3].

The macrocyclic polyamine 1,4,7-trimethyl-1,4,7,10-tetraazacyclododecane [LH = (Me3TACD)H] formed adducts with tetramethyl-silazides [M{N(SiHMe2)2}] (M = Li, Na, K) of light alkali metals. Upon heating, intramolecular dehydrocoupling occurred to give [M{(L)SiMe2N(SiHMe2)}]. BPh3 induced facile ring-opening of THF when reacted with [Li{(L)SiMe2N(SiHMe2)}].

Molecular aluminum hydride [(L)AlH2] (L = Me3TACD) reacted with 2 equiv. of BPh3 in THF or THP to give the cationic alkoxides [(L)Al(OR)][HBPh3] (R = nBu, nPent) by facile ring-opening of the cyclic ethers. The Cα–O bond cleavage which involves the isolable intermediate [(L)AlH][HBPh3] is a result of hydride transfer to Cα from [HBPh3]−.

We fabricated a simple sensor system for qualitative analysis of glycan-mediated interactions. Our main aim was to establish a ronbbust system that allowes drop-tests without complex fluidics. The test system should be usable in routine analytics in the future and bear sufficient sensitivity to detect binding events in the nanomolar range. For this, we employed optical ring resonators and coated them with high avidity glycopolymers based on N-acetylglucosamine (GlcNAc). These hydrophilic polymers are also very feasible in preventing unspecific protein adsorption. Drop-on binding studies with suitable lectins showed that glycopolymers were specifically recognized by a lectin with GlcNAc-specificity and prevented unspecific protein interactions very well. The system could be elaborated in the future for detection of glycan-mediated interactions in the biomedical field and is promising in means of multiplexed analysis and usage in routine analysis.

Glycan‐protein interactions are essential biological processes with many disease‐related modulations and variations. One of the key proteins involved in tumor progression and metastasis is galectin‐3 (Gal‐3). A lot of effort is put into the development of Gal‐3 inhibitors as new therapeutic agents. The avidity of glycan‐protein interactions is strongly enhanced by multivalent ligand presentation. Multivalent presentation of glycans can be accomplished by utilizing glycopolymers, which are polymers with pendent glycan groups. For the production of glycopolymers, glycomonomers are synthesized by a regioselective, microwave‐assisted approach starting from lactose. The resulting methacrylamide derivatives are polymerized by RAFT and immobilized on gold surfaces using the trithiocarbonate group of the chain transfer agent. Surface plasmon resonance spectroscopy enables the label free kinetic characterization of Gal‐3 binding to these multivalent glycopolymers. The measurements indicate oligomerization of Gal‐3 upon exposure to multivalent environments and reveal strong specific interaction with the immobilized polymers.

Glykopolymere sind synthetische und natürlich vorkommende Polymere, die eine Glykaneinheit in der Seitenkette des Polymers tragen. Glykane sind durch die Glykan-Protein-Wechselwirkung verantwortlich für viele biologische Prozesse. Die Beteiligung der Glykanen in diesen biologischen Prozessen ermöglicht das Imitieren und Analysieren der Wechselwirkungen durch geeignete Modellverbindungen, z.B. der Glykopolymere. Dieses System der Glykan-Protein-Wechselwirkung soll durch die Glykopolymere untersucht und studiert werden, um die spezifische und selektive Bindung der Proteine an die Glykopolymere nachzuweisen. Die Proteine, die in der Lage sind, Kohlenhydratstrukturen selektiv zu binden, werden Lektine genannt. In dieser Dissertationsarbeit wurden verschiedene Glykopolymere synthetisiert. Dabei sollte auf einen effizienten und kostengünstigen Syntheseweg geachtet werden. Verschiedene Glykopolymere wurden durch funktionalisierte Monomere mit verschiedenen Zuckern, wie z.B. Mannose, Laktose, Galaktose oder N-Acetyl-Glukosamin als funktionelle Gruppe, hergestellt. Aus diesen funktionalisierten Glykomonomeren wurden über ATRP und RAFT-Polymerisation Glykopolymere synthetisiert. Die erhaltenen Glykopolymere wurden in Diblockcopolymeren als hydrophiler Block angewendet und die Selbstassemblierung in wässriger Lösung untersucht. Die Polymere formten in wässriger Lösung Mizellen, bei denen der Zuckerblock an der Oberfläche der Mizellen sitzt. Die Mizellen wurden mit einem hydrophoben Fluoreszenzfarbstoff beladen, wodurch die CMC der Mizellenbildung bestimmt werden konnte. Außerdem wurden die Glykopolymere als Oberflächenbeschichtung über „Grafting from“ mit SI-ATRP oder über „Grafting to“ auf verschiedene Oberflächen gebunden. Durch die glykopolymerbschichteten Oberflächen konnte die Glykan Protein Wechselwirkung über spektroskopische Messmethoden, wie SPR- und Mikroring Resonatoren untersucht werden. Hierbei wurde die spezifische und selektive Bindung der Lektine an die Glykopolymere nachgewiesen und die Bindungsstärke untersucht. Die synthetisierten Glykopolymere könnten durch Austausch der Glykaneinheit für andere Lektine adressierbar werden und damit ein weites Feld an anderen Proteinen erschließen. Die bioverträglichen Glykopolymere wären alternativen für den Einsatz in biologischen Prozessen als Transporter von Medikamenten oder Farbstoffe in den Körper. Außerdem könnten die funktionalisierten Oberflächen in der Diagnostik zum Erkennen von Lektinen eingesetzt werden. Die Glykane, die keine selektive und spezifische Bindung zu Proteinen eingehen, könnten als antiadsorptive Oberflächenbeschichtung z.B. in der Zellbiologie eingesetzt werden., Glycopolymers are synthetic and naturally occurring polymers that carry a gylcan unit in the side chain of the polymer. Glycans are responsible for many biological processes due to the glycn-protein interaction. The involvement of glcans in these biological processes enables the imitation and analysis of interactions by suitable model coumponds, e.g. glycopolymers. This system of glycan-protein interaction will be investigated and studied by glycopolymers in order to demonstrate the specific and selective binding of proteins to glycopolymers. The proteins that are able to selectively bind carbohydrate structures are called lectins. In this dissertation different glycopolymers were synthesized. Care should be taken to ensure an effficient and cost-effective synthesis route. Different glycopolymers were produced by functionalized monomers with different sugars, such as mannose, lactose, galactose or N-acetyl-glucosamine as functional group. From these functionalized glycomonomers, glycopolymers were synthesized via ATRP and RAFT polymerization. The glycopolymers obtained were used as hydrophilic blocks in diblock copolymers and self-assembly in aqueous solution was investigated. In aqueoussolution, the polymers formed micelles in which the sugar block sits on the surface of the micelles. The micelles were loaded with a hydrophobic fluorescent dxe, which made it possible to determine the CMC of micelle formation. In additiom, the glycopolymers were bound to various surfaces as surface coatings via “grafting from” with SI-ATRP or via “grafting to”. Through the glycopolymer-coated surfaces, the glycan-protein interaction could be investigated by spectroscpic measurement methods such as SPR and microring resonators. The specific and selective binding of lectins to the glycopolymers was detected and the binding strength was investigated. The synthesised glycopolymers could become adressable for other lectins by exchanging the glycan unit and thus open up a broad field of other proteins. The biocompatible glycopolymers would be an alternative for use in iological processes as transporters of drugs or dyes into the body. In addtion, the functionalised surfaces could be used in diagnostics for regognition of lectins. The glycan, which do nit bind selectively and specifically to proetins, could be used as anit-adsoptive surface coatings, e.g. in cell biology.

Light alkali metal hydridotriphenylborates M[HBPh3] (M = Li, Na, K), characterized as tris{2-(dimethylamino)ethyl}amine (L) complexes [(L)M][HBPh3], act as efficient catalysts for the chemoselective hydroboration of a wide range of aldehydes and ketones using pinacolborane HBpin. The lithium derivative showed a remarkably high TOF of ≥17 s(-1). These compounds also catalyze the hydroborative reduction of CO2 to give formoxyborane HCO2Bpin without any over-reduction.

Alkali metal hydridotriphenylborates [(L

Copper(I) and copper(II) complexes were covalently linked to an engineered variant of the transmembrane protein Ferric hydroxamate uptake protein component A (FhuA ΔCVFtev). Copper(I) was incorporated using an N-heterocyclic carbene (NHC) ligand equipped with a maleimide group on the side arm at the imidazole nitrogen. Copper(II) was attached by coordination to a terpyridyl ligand. The spacer length was varied in the back of the ligand framework. These biohybrid catalysts were shown to be active in the Diels–Alder reaction of a chalcone derivative with cyclopentadiene to preferentially give the endo product.

Synthetic access to the zerovalent palladium complexes {[(o-Ph2PC6H4)2BPh]Pd(L)} (L = pyridine (8a), 2,6-lutidine (8b)) is reported. Structural characterization and DFT analysis of 8a revealed a strong Pd→B interaction, which appears to inhibit oxidative addition reactions. Activation of allyl acetate is possible by reversible transfer of the acetate leaving group to the ligand’s borane functionality. Catalytic activity in the allylic substitution of allyl acetate with HNEt2 is sensitive to the presence of free acetate, which reduces borane inhibition by reversible borate formation.

Resume Objectifs. – Le but de ce travail etait d'etudier le nombre de grains migrants, les sites de migration et les eventuels facteurs de prediction de migration apres curietherapie de prostate par implantation de grains libres d'iode 125. Patients et methodes. – Les dossiers des 170 patients traites consecutivement par l'equipe de l'institut Curie–hopital Cochin–hopital Necker, du 1 er septembre 2001 au 31 aout 2002, ont ete analyses. Ont ete pris en compte les grains migrants pulmonaires visualises sur le cliche de thorax effectue systematiquement deux mois apres l'implantation, ainsi que les grains recuperes dans les urines (apres filtrage de ces dernieres) et le sperme (rapports proteges). Resultats. – Sur 12 179 grains implantes, 44 ont migre (0,36 %), la majorite (32/44, 73 %) vers les poumons. Ces migrations ont interesse 35 patients, soit 21 % des cas traites durant cette periode. Dans la grande majorite des cas (77 %), un seul grain a migre. Une relation significative ( p = 0,04) a ete retrouvee entre le nombre de grains migrants et le nombre de grains implantes (ou le volume prostatique, ces deux parametres etant lies de facon etroite). Plus specifiquement, une relation significative ( p = 0,02) a pu etre mise en evidence entre le nombre de grains implantes en peripherie et le nombre de grains migrants pulmonaires. Conclusion. – Le pourcentage de grains migrants dans cette serie reste l'un des plus bas de la litterature pour la technique des grains libres. La migration en general d'un seul grain n'a aucune consequence clinique, et aucun effet deletere (ou tres peu) sur la distribution de dose. Neanmoins, la nette predominance des migrations pulmonaires dans notre serie nous a pousse a modifier legerement notre technique d'implantation. Nous evitons actuellement dans toute la mesure du possible d'implanter les grains de facon trop peripherique, du fait du risque de migrations vers les plexus veineux periprostatiques, puis vers les poumons.

Gas detectors have come a long way since the first commercial detector; yet, some though safe and efficient, they are expensive or pose high maintenance cost, others are simple and cheap but lack safety, mobility and efficiency. Gas Ascertainment via Smartphone (GAS) is the recommended detector that is far more advanced, and offers safety, mobility and accuracy, and is affordable by average factory owner. It is a combination of a smartphone application and a small robot. Running on an Android smartphone, the mobile application communicates with a single-board computer placed within the robot. The application's purpose is to receive a live camera stream from the robot, and alerts the user when the gas sensors detect dangerous concentrations. The user controls the movement of the robot through touch buttons found on the smartphone's screen. GAS is expected to make factories and storage departments safer. In addition to being affordable, the user can control the robot's movement via smartphone, over Wi-Fi, from a safe distant, far from the harmful gases. In addition, the user does not need to have any technical background or undergo training to operate the said detector. Moreover, in the future many features can be added to the system to make it satisfy the users' need, such as transmitting data over the Internet, porting the mobile application to other mobile operating systems, and making the robot follow the gas' leakage source.

Background: New chemopreventive strategies for ulcerative colitis (UC)-associated dysplasia and cancer have to be evaluated. Taurolidine (TRD) has anti-inflammatory, anti-proliferative and anti-neoplastic properties with almost absent toxicity. The aim of the study was to determine whether TRD decreases dysplasia in the well-characterized Dextran Sulfate Sodium - Azoxymethane (DSS-AOM) animal model for UC-associated carcinogenesis. Material and Methods: The DSS-AOM model of carcinogenesis was induced in female inbred C57BL/6 mice. Half of the mice were treated with TRD, the other served as control. After 100 days macroscopic, histological and immunhistochemical (β-Catenin, E-Cadherin, SOX9, Ki-67, Cyclin-D1) examination of the colon was performed. Results: Incidence, multiplicity, grading and growth pattern of adenomas did not differ significantly between TRD and control group. In all animals, inflammatory changes were absent. Immunhistochemistry revealed increased expression of Ki-67, β-catenin, SOX9 and Cyclin-D1 in adenomas compared to normal mucosa - without significant difference between TRD and control treatment. Conclusion: Oral administration of TRD has no impact on DSS-induced colitis-associated carcinogenesis. However, SOX9 and Cyclin-D1 representing key members of the Wnt pathway have not yet been described in the DSS-AOM model of carcinogenesis - underlining the importance of this oncogenic pathway in this setting.

To study the number of migrating seeds, the anatomical site of migration and possible predictive parameters of migration, after prostate cancer brachytherapy using a loose-seed (I125) implantation technique.The charts of the 170 patients consecutively treated by the Institut Curie/Hospital Cochin/Hospital Necker Group between September 1, 2001 and August 31, 2002, were analysed. All seeds having migrated to the lungs and seen on the chest X-ray systematically performed at 2 months, have been recorded, as well as the seeds lost by the urines (after sieving) or in the sperm (condom).Among 12,179 implanted seeds, 44 were found to have migrated (0.36%). Most of the migrating seeds (32/44; 73%), were found in the lungs. Overall, one or several seed migrations were observed in 35 patients (21% of the total number of patients in this series). In the majority of cases (77%), only one seed migrated. A significant relationship (P = 0.04) was found between the number of migrating seeds and the number of implanted ones (or with the prostate volume, but those two parameters were closely linked in our series). More specifically, a significant relationship (P = 0.02) could be demonstrated between the number of seeds implanted at the periphery of the prostate and the number of seeds migrating to the lungs.The percentage of migrating seeds observed in this series is low, actually one of the lowest found in the literature when using the loose-seed technique. There was no clinical consequences and the loss of-usually-only one seed is very unlikely to alter the quality of the dose distribution. However, the predominance of pulmonary migrations in our series led us to slightly modify our implantation technique. We now try to avoid too "peripheral" seed implantations, due to the risk of migration towards the periprostatic veins, and subsequently to the lungs.