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A nitronyl nitroxide unit (NN) was linked with a triphenylamine‐based condensed polycyclic skeleton DOTT to form a radical substituted donor NN‐DOTT. X‐ray crystal structure analysis demonstrated a flat bowl shape of the DOTT unit. EPR spectra showed the localization of electron spin on the NN unit. Chemical oxidation of the DOTT unit produced radical‐substituted radical cation salts NN‐DOTT+ ⋅ SbF6− and NN‐DOTT+ ⋅ FeBr4− that are stable under ambient conditions. The magnetic behavior of NN‐DOTT+ ⋅ SbF6− is characterized by the strong intramolecular ferromagnetic interaction between NN and DOTT+. The X‐ray structural analysis of NN‐DOTT+ ⋅ FeBr4− shows planar structure of DOTT and 1D mixed‐stack column of NN‐DOTT+ and FeBr4−. Magnetic measurements established that NN‐DOTT+ ⋅ FeBr4− undergoes magnetic phase transition into a weak ferromagnet at 7 K. [ABSTRACT FROM AUTHOR]

We prepared dicopper, disilver, and tetragold clusters ligated with (nitronyl nitroxide)‐substituted amidinate (NN‐amidinate). NN‐substituted amidine was prepared from N,N′‐diphenylcarbodiimide via a nucleophilic reaction with nitronyl nitroxide as a radical anion. The NN‐amidinate ligand was generated by treatment with an appropriate base, and subsequent addition of copper(I), silver(I), or gold(I) sources gave the respective metal cluster systems of Cu2‐(NN‐amidinate)2, Ag2‐(NN‐amidinate)2, or Au4‐(NN‐amidinate)4. These radical‐metal clusters exhibited excellent stability, even in solution under aerated conditions, making them easy to handle. Single crystals were obtained by recrystallization from suitable solvent systems. The spin structures of the cluster systems were investigated by ESR spectroscopy and magnetic susceptibility measurements, which indicated the existence of weak intramolecular, spin‐spin interactions between the NN moieties. [ABSTRACT FROM AUTHOR]

A triplet ground‐state diradical molecule, bis(nitronyl nitroxide)‐substituted diphenyldihydrophenazine (1..), that can be converted into a one‐electron oxidized species, 1...+, in the quartet ground state has been developed. Surprisingly, these species, 1.. and 1...+, can be used under ambient conditions because they are reasonably stable under aerobic conditions, even in solution. The temperature‐dependent magnetic susceptibilities reveal that 1.. and 1...+ are in the triplet state, with a weak exchange interaction (J1/kB = +3.1 K) and quartet ground state with a strong exchange interaction (J2/kB = +160 K), respectively. The interconversion between the neutral and one‐electron oxidized species can be realized through electrochemical reactions. Significantly different absorption bands in the near‐IR region newly appeared in the electronic spectra acquired during electrochemical oxidation/reduction. [ABSTRACT FROM AUTHOR]

Small-cell lung carcinoma releases progalanin. The released progalanin is activated via a nonclassical processing pathway, being processed into an active form of galanin (1-20) by plasmin in extracellular components. Plasmin is produced from plasminogen activators. To clarify the regulation of progalanin via plasminogen activation by urokinase and tissue-plasminogen activator (t- PA), we investigated the regulation mechanism for urokinase and t- PA expression and their effect on galanin activation. Additionally, we studied the effect of activated galanin on angiogenesis. To determine the effect of cell density, we measured the expression levels of urokinase and t- PA using real-time PCR and plasminogen/gelatin zymography in a cell culture. The urokinase expression increased under both high cell density and presence of cell membrane fractions. However, urokinase increments induced by conditioned medium were low. These results indicate that expression of plasminogen activators is regulated by cell membrane factors. We used tumor-bearing mice to clarify the expression of plasminogen activators and galanin activation. Real-time PCR showed that urokinase was substantially higher in the central parts of tumors compared to the periphery, and this was confirmed by plasminogen/gelatin zymography. To evaluate the biological effect of plasminogen activators on tumor growth, we used tranexamic acid as a plasminogen inhibitor. Tranexamic acid decreased galanin (1-20) and the hemoglobin content of tumors and suppressed tumor growth. Additionally, galanin had no effect on the hemoglobin content of tumors derived from cells lacking GALR2. These results demonstrate the regulation of urokinase expression in tumors through progalanin activation in extracellular compartments, and confirm that galanin plays a role in angiogenesis. [ABSTRACT FROM AUTHOR]

Tetragocarbones A and B were isolated from the propolis of an Australian stingless bee, Tetragonula carbonaria. These largely planar structures were proposed as a result of NMR analysis as well as comparison of their NMR data with those of related monomeric phloroglucinol derivatives. To elucidate relative and absolute stereochemistry of tetragocarbone A, the synthesis of the proposed structure of tetragocarbone A was performed. As a result, the synthetic compound bearing stereogenic centers 1 R*,3 R*,6 S* was identical with naturally occurring tetragocarbone A. The absolute stereochemistry of tetragocarbone A was established to be 1 R,3 R,6 S by chiral HPLC separation and X-ray analysis. Comparison of the NMR data of tetragocarbone A with that of tetragocarbone B indicated that tetragocarbone B would be a natural congener of tetragocarbone A. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this study was to examine the abrasive and cleaning effects of melamine foam and other cleaning agents on the surfaces of composite resin artificial tooth specimens. Materials and Methods A stained composite resin artificial tooth in a used denture was cleaned using a denture brush and melamine foam, and the stain removal effect was evaluated macroscopically. Next, 5 types of cleaning material (fourfold-compression melamine foam, MEL; brush with water, BRU; denture dentifrice without abrasive, POL; denture dentifrice with abrasive, TAF; conventional dentifrice, AQU) and 15 plate-shaped specimens made of composite resin for artificial teeth were used for wear tests. The surface roughness was measured using a laser scanning microscope. Furthermore, the surface properties were observed using a digital microscope. Surface roughness data were analyzed by two-way ANOVA followed by Tukey's test. Results Artificial tooth stains that could not be removed by brushing became removable using melamine foam. With regard to surface roughness in the context of the wear test, significant differences were not indicated between MEL and POL, whereas BRU-, TAF-, and AQU-treated specimens showed significantly increased surface roughness ( p < 0.05). In the comparison among the cleaning materials, TAF- and AQU-treated specimens showed significantly rougher surfaces than those treated with MEL, BRU, and POL ( p < 0.05). Conclusions Macroscopic observations suggest that melamine foam would be effective for the removal of stains on composite resin artificial teeth. Traces of wear were not observed in specimens treated with melamine foam and the denture dentifrice not containing abrasives. It was suggested that these two materials would be desirable and useful to use for composite resin tooth cleaning. [ABSTRACT FROM AUTHOR]

Radikale Lösung: Pentacenderivate sind wegen ihrer photochemischen Unbeständigkeit und schlechten Löslichkeit von Anwendungen in der molekularen Elektronik ausgeschlossen. Pentacenderivate mit stabilen radikalischen Substituenten Y (1 a und 2 a), die in organischen Lösungsmitteln unter Umgebungslicht eine Lebensdauer von bis zu 2077 min aufweisen, umgehen diese Probleme. Entsprechende nichtradikalische Derivate (1 b und 2 b) zersetzen sich unter Lichteinstrahlung. [ABSTRACT FROM AUTHOR]

Objectives: Few studies have examined the psychosocial impact of breast cancer and its treatment on African women who come from a poverty-stricken, uneducated background in a developing country. The purpose of this study was to describe the specific psychosocial effects of breast cancer on married African women in order to help physicians educate and counsel future women and their families in Northwestern Nigeria. Methods: Two semi-structured, self-report questionnaires were given to 81 consenting married African women treated with unilateral total mastectomy secondary to operable breast cancer at the Ahmadu Bello University Teaching Hospital. Questionnaires were answered at the time of the diagnosis and treatment consultation and at 6 months postmastectomy and included questions about demographics, frequency of conjugal relations and how the woman's sense of femininity was affected. Marital status was also tracked up to 3 years. Results: Six months after surgery, the survey responses revealed that 67.9% of women felt inadequate as a woman because of the mastectomy and that 79.0% experienced a decrease in frequency of conjugal relations. Three years after primary breast cancer treatment, 61.7% of the participants were still married while 38.3% reported being divorced/separated from their husbands. Conclusions: These results indicated that married African women face significant physical, emotional and social changes and difficulties following primary breast cancer treatment. Culturally sensitive therapeutic groups and interventions should be established to help Nigerian women with breast cancer and their spouses and families understand and cope with the disease and its long-term health and quality-of-life implications. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The aim of this postal survey was to highlight differences in temperament and behaviour between 32 toddlers in Japanese families living temporarily in London and 36 in British families, all in London. Mothers completed questionnaires about demography, perinatal events, and their child's temperament and behaviour. UK toddlers were described as exhibiting fewer behavioural symptoms than Japanese toddlers. Significantly more of the Japanese toddlers scored above the cutoff on the Behaviour Check List, indicating higher levels of behavioural disturbance. An interesting item is ‘sleeping with parent’, which occurs commonly in Japanese families and is considered to be normal for that culture. On the Toddler Temperament Scale the Japanese toddlers proved more distractable and more intense than the UK toddlers when age had been allowed for. It was of interest that Japanese girls proved more distractable than Japanese boys and UK girls. Possible explanations for the differences are advanced. [ABSTRACT FROM AUTHOR]

This method selectively deprotects N-phenylcarbamoyl groups while tolerating a variety of other protecting groups and functionalities. [ABSTRACT FROM AUTHOR]