Publications by authors named "Marciniak H"

Polymer micelles are an attractive means to solubilize water insoluble compounds such as drugs. Drug loading, formulations stability and control over drug release are crucial factors for drug-loaded polymer micelles. The interactions between the polymeric host and the guest molecules are considered critical to control these factors but typically barely understood.

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A tetraphenylsquaraine was synthesized whose structure was elucidated by single crystal X-ray structure analysis. Unlike all known indolenine squaraines, the tetraphenylsquaraine shows an unusual nonplanar structure with the four phenyl groups pointing away from the squaric acid core in order to avoid steric congestion. This tetraphenylsquaraine was polymerized by a Yamamoto coupling to form a conjugated polymer with Xn = 38.

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The ground state tautomerism and excited state intramolecular proton transfer (ESIPT) of 10-hydroxybenzo[h]quinoline (HBQ) and its nitro derivatives, 7-nitrobenzo[h]quinolin-10-ol (2) and 7,9-dinitrobenzo[h]quinolin-10-ol (3), have been studied in acetonitrile using steady state as well as time dependent spectroscopy and quantum-chemical calculations. In addition to the enol form absorbance in the range 360-390 nm, the absorption spectra of 2 and 3 exhibit a red shifted band at ∼450 nm. Chemometric data processing, based on individual band decomposition, allowed us to estimate the position of the ground state enol-keto tautomeric equilibrium (ΔG values of 1.

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The solvent dependent excited state dynamics of 4-hydroxy-3-(piperidin-1-ylmethyl)-1-naphthaldehyde (compound 2), a candidate for a molecular switch based on intramolecular proton transfer, was investigated by ultrafast spectroscopy and quantum-chemical calculations. In acetonitrile a mixture of molecules in the enol and zwitterionic proton transfer (PT) form exists in the ground state. However, the zwitterion is the energetically favored one in the electronically excited state.

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A series of naphthaldehydes, including a Mannich base, have been investigated by UV-Vis spectroscopy, NMR and theoretical methods to explore their potential tautomerism. In the case of 4-hydroxy-1-naphthaldehyde concentration dependent deprotonation has been detected in methanol and acetonitrile. For 4-hydroxy-3-(piperidin-1-ylmethyl)-1-naphthaldehyde (a Mannich base) an intramolecular proton transfer involving the OH group and the piperidine nitrogen occurs.

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Purpose: The multicentre response-adapted paediatric Hodgkin lymphoma trial GPOH-HD95 (1995-2001, 925 patients) was followed by the 'HD-Interval' period (2001-2002, 203 patients). During this period, treatment was recommended according to GPOH-HD95 protocol with only minor changes. Central review and treatment planning as in HD95, however, had to be omitted in the absence of funding.

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Unlabelled: PURPOSE To minimize the risk of late effects in pediatric Hodgkin lymphoma (HL) by omitting radiotherapy (RT) in patients in complete remission (CR) after chemotherapy and reducing the standard radiation dose to 20 Gy in patients in incomplete remission.

Patients And Methods: Between 1995 and 2001, 925 patients with classical HL (cHL) were registered from seven European countries in German Society of Pediatric Oncology and Hematology Hodgkin Lymphoma Trial 95. Patients in treatment group 1 (TG1; early stages) received two cycles of vincristine, prednisone, procarbazine, and doxorubicin or vincristine, prednisone, etoposide, and doxorubicin chemotherapy; additional two or four cycles of cyclophosphamide, vincristine, prednisone, and procarbazine were added in TG2 (intermediate stages) or TG3 (advanced stages), respectively.

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Perylene bisimides (PBIs) are excellent dyes and versatile building blocks for supramolecular structures. Only recently have PBIs been shown to depict absorption characteristics of J-aggregates. We apply electronic structure calculations and femtosecond pump-probe spectroscopy to the monomeric, bay-substituted building-block of a PBI aggregate in dichloromethane to investigate its electronically excited states in order to provide the ingredients for the description of excitons in the aggregates and their annihilation processes.

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The dynamics and mobility of excitons in J-aggregates of perylene bisimides are investigated by transient absorption spectroscopy with a time resolution of 50 fs. The transient spectra are compatible with an exciton delocalization length of two monomers and indicate that vibrational and configurational relaxation processes are not relevant for the spectroscopic properties of the aggregates. Increasing the pump pulse energy and in that way the initial exciton density results in an accelerated signal decay and pronounced exciton-exciton annihilation dynamics.

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Background: Idiopathic thrombocytopenic purpura (ITP) is the most prevalent acquired hemorrhagic diathesis in children characterised by antibody-mediated destruction of platelets. ITP is generally a self-limiting benign disorder but despite this good prognosis, ITP carries the risk of severe bleeding (mainly intracranial) that may threaten the child's life.

Case Report: We describe a case of a 5-year-old girl with idiopathic thrombocytopenic purpura in the course of EBV infection with massive cerebral and intraventricular hemorrhage and fatal outcome.

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Introduction: Tuberous sclerosis complex (TSC) is a genetic disorder characterised by lesions affecting brain, skin, eyes and internal organs--kidneys, heart, liver and lungs. Renal involvement in individuals with TSC is common and potentially serious, includes angiomyolipomas and cystic lesions. There may also be an increased risk of renal cell carcinoma.

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Purpose: A possible complication in regard to osteosynthetic treatment of a lower radius fracture with a locking plate is perforation of the articular surface by screws or a malpositioned ulnar fragment. In order to create good conditions for a homogeneous, reproducible X-ray picture for post-operative imaging control, an appliance for the production of standardised X-ray views has been devised.

Materials And Methods: The X-ray device was constructed at an angle of 20 degrees to the camera.

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The exciton dynamics in microcrystalline pentacene films is investigated by transient absorption measurements with 30 fs time resolution. It is found that the emission from photoexcited Frenkel excitons decays within 70 fs due to the ultrafast formation of an excitonic species with a strongly reduced transition dipole to the ground state and an absorption dipole in the plane of the film. We propose that an excimer exciton is formed and stabilized by changes of the local crystal structure.

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The authors have developed a cellular analysis platform, based on encoded microcarriers, that enables the multiplexed analysis of a diverse range of cellular assays. At the core of this technology are classes of microcarriers that have unique, identifiable codes that are deciphered using CCD-based imaging and subsequent image analysis. The platform is compatible with a wide variety of cellular imaging-based assays, including calcium flux, reporter gene activation, cytotoxicity, and proliferation.

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Background: In 5 consecutive pediatric and adolescent Hodgkin's disease trials DAL-HD since 1978 the invasive diagnostic procedures and the radiotherapy have gradually been reduced and chemotherapy modified to minimize toxicity and the risk of late effects. Since 1982 the overall survival increased up to 95%. In this trial the possibility of reducing local radiation doses to 20 Gy in patients with good response to chemotherapy and omitting radiotherapy totally for patients with complete remission after chemotherapy was tested.

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Purpose: A multinational trial on pediatric Hodgkin's disease (HD) with the aim to reduce the risk of long-term toxicity of combined modality treatment by restricting dose and volume of radiation therapy (RT) while maintaining the excellent treatment results of previous German multicenter trials (DAL-HD82-90).

Methods And Materials: Patients were treated according to stage of disease (CS) and defined risk factors in three treatment groups (TG) with 2, 4, or 6 cycles of combination chemotherapy. When a complete remission (CR) had been achieved, treatment was terminated without RT independent of initial stage or tumor bulk.

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Based on concepts of the successful German-Austrian pediatric Hodgkin studies DAL-HD 78 until-90, a new trial was initiated addressing the question whether radiotherapy can be further reduced or can be omitted in case of complete remission after initial chemotherapy, aiming at reduction of sequelae after radiotherapy, especially radiogenic second malignancies. In respect to CHEMOTHERAPY patients are stratified into 3 therapy groups (TG) according to stage and gender: 2 courses of OPPA (girls) or OEPA (boys) in TG1 (stage IA/B, IIA), and in addition 2 (TG2: stage IEA/B, IIEA, IIB, IIIA) or 4 (TG3: stage IIEB, IIIEA/B, IIIB, IVA/B) COPP courses. Boys with stage IIIB and IIIEB receive OPPA instead of OEPA.

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Background: The course of tissue changes in acute myocarditis in humans is not well understood. Diagnostic tools currently available are unsatisfactory. We tested the hypothesis that inflammation is reflected by signal changes in contrast-enhanced magnetic resonance imaging (MRI).

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Guidelines and standards supplementing the German "Röntgenverordnung" initiated a complex system of quality control in diagnostic radiology. Cost and profit are analysed for two hospitals of comparable size (Klinikum Buch and Klinikum Nürberg). The considerable expenses that must be incurred for measuring devices, equipment, working time and extra charges on the one hand, are the items that are opposed to achieving a higher image quality and dose reduction on the other.

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Purpose: To compare the x-ray images made by the Kodak InSight Pediatric Imaging System (InSight P) with conventional film-screen systems in pediatric chest radiography.

Material And Methods: The comparison involved chest radiographs made using Quanta-Fast-Detail/Cronex 4 (DuPont), Trimax 16/XDA (3 M) and DuPont UVR/UVL systems. The image quality of critical structures and the physical parameters of quantum interference, contrast and resolution were assessed.

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Due to its diagnostic accuracy as well as safe and accurate puncture technique CT can be used advantageously for percutaneous sclerosing therapy of renal cysts. CT-guided sclerosing therapy with pantopaque emulsions was carried out in 100 patients on an outpatient basis with altogether 107 solitary renal cysts. There were indications in all cases.

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43 mediastinal tumours differing by genesis, operability, and localisation and handled between 1970 and 1985 are reported in this paper. They called for differentiated diagnosis and therapy. Most of them (21) were of neurogenic origin.

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