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Make your OLED fluorescent: an aromatic molecule based on a spiro-acridine derivative was designed, and its photoluminescence and electroluminescence were characterized. By combining the donor and acceptor moieties a small energy gap between the lowest singlet and triplet states was achieved. This design leads to an organic light-emitting diode (OLED) that rivals phosphorescent devices regarding exciton generation efficiency.

Characteristic triboluminescence from a lanthanide coordination polymer with a non-centrosymmetric structure is reported. The lanthanide coordination polymer is composed of luminescent EuIII ions and bidentate phosphane oxides, poly[3,3′-bis(diphenylphosphoryl)-2,2′-bipyridine][tris(hexafluoroacetylacetonate)]europium (poly-Eu-BIPYPO) crystals. The coordination geometry of poly-Eu-BIPYPO is categorized as an asymmetric eight-coordinate square antiprism (8-SAP). The space group of the crystal is also classified as the non-centrosymmetric Cc, which is suitable for piezoelectricity and triboluminescence. The photoluminescence quantum yield of poly-Eu-BIPYPO crystals excited at 380 nm is found to be 61 %. Triboluminescence of the lanthanide coordination polymer is observed upon breaking, even at ambient temperature and in daylight. The remarkable triboluminescence phenomenon and geometrical structure of lanthanide coordination polymer are demonstrated.

Novel EuIII complexes with bidentate phosphine oxide ligands containing a bipyridine framework, i.e., [3,3′-bis(diphenylphosphoryl)-2,2′-bipyridine]tris(hexafluoroacetylacetonato)europium(III) ([Eu(hfa)3(BIPYPO)]) and [3,3′-bis(diphenylphosphoryl)-6,6′-dimethyl-2,2′-bipyridine]tris(hexafluoroacetylacetonato)europium(III) ([Eu(hfa)3(Me-BIPYPO)]), were synthesized for lanthanide-based sensor materials having high emission quantum yields and effective chemosensing properties. The emission quantum yields of [Eu(hfa)3(BIPYPO)] and [Eu(hfa)3(Me-BIPYPO)] were 71 and 73%, respectively. Metal-ion sensing properties of the EuIII complexes were also studied by measuring the emission spectra of EuIII complexes in the presence of ZnII or CuII ions. The metal-ion sensing and the photophysical properties of luminescent EuIII complexes with a bidentate phosphine oxide containing 2,2′-bipyridine framework are demonstrated for the first time.

Structures and photophysical properties of f-block metal complexes with tandem-connected tridentate phosphane oxide ligands, {bis[o-(diphenylphosphoryl)phenyl]phenylphosphane oxide}tris(hexafluoroacetylacetonato)europium(III) [Eu(hfa)3(DPPPO)], {bis[o-(diphenylphosphoryl)pyridyl]phenylphosphane oxide}tris(hexafluoroacetylacetonato)europium(III) [Eu(hfa)3(DPPYPO)] and {bis[o-(diphenylphosphoryl)benzothienyl]phenylphosphane oxide}tris(hexafluoroacetylacetonato)europium(III) [Eu(hfa)3(DPBTPO)], are reported. The coordination geometries of Eu(hfa)3(DPPPO) and Eu(hfa)3(DPBTPO) provide characteristic distorted, capped square antiprism structures with nine-coordinate oxygen atoms. The emission properties related to the electric transition are characterized by the emission spectra, the emission quantum yields, the emission lifetimes, and the radiative and non-radiative rate constants. EuIII complexes with tridentate phosphane oxide ligands offer relatively high emission quantum yields (> 60 % in [D6]acetone) due to their low-symmetric and low-frequency vibrational structures. The electric dipole transition intensities in the emission spectra depend on the chemical structures of tridentate phosphane oxides. The characteristic photophysical properties of polyhedral f-block metal complexes, nine-coordinate EuIII complexes with tridentate phosphane oxide, are demonstrated for the first time.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Triangle terarylene derivatives based on the 4,5-diarylthiazole structure have been synthesized and their photochromic properties have been studied both in solution and in the crystalline state. The thiazolyl-substituted terarylenes displayed reversible photochromism in solution, with photocyclization quantum yields as high as 60 %, while a 4,5-dithienylthiazole derivative underwent photochromic reaction even in the single-crystal state, although a 4,5-dithiazolylthiazole (terthiazole) showed no photochromic reaction in the crystalline phase. The difference in photochromic reactivity between the 4,5-dithienylthiazole and the 4,5-dithiazolylthiazole was found by X-ray crystallographic analyses to originate from conformational differences in the crystalline state. The thermal cycloreversion activation energies in the solution phase were measured for thiazolyl-substituted terarylenes and for a corresponding terthiophene derivative. The activation energy for the transition from photogenerated closed-ring isomer to open-ring isomer increased with the number of substitutions of thiazole unit for thiophene. The lower aromatic stabilization energy of thiazole in relation to that of thiophene was considered to be responsible for the thermal stability of the closed-ring isomers of thiazolyl-substituted terarylenes.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

An architecture for a general purpose digital signal processor has been developed that enables the specification of peripherals and the core part to be easily changed for specific applications. an evaluation chip LSI providing 24-bit fixed-point arithmetic was created in order to verify the performance. This digital signal processor (DSP) basically uses RISC-type architecture in order to simplify the hardware structure and provides two types of instruction sets, called RISC-type and DSP-type instructions, to maintain the benefit of the original DSP. the RISC-type instruction set consists of several types of single-task operating commands: arithmetic, logical, data transfer, branch, etc. It provides wide operand flexibility. On the other hand, the DSP-type instruction set consists of parallel operating commands as provided for conventional DSP which execute several data processing and data transfer operations. However, operand flexibility is restricted by providing these two types of instruction sets in one LSI and a higher performance can be achieved than with conventional DSPs which have the same bit length and only one instruction set.

Patients with anorexia nervosa (AN) tend to have renin-angiotensin-aldosterone (RAA) abnormalities caused by abnormal behaviors such as strict dieting, fasting, vigorous exercise, self-induced vomiting and abuse of laxatives and/or diuretics. Adrenal responsiveness to angiotensin II (A II) was studied in 13 AN patients before and after therapy and in 6 normal sex- and age-matched controls: adrenal responses to postural change (1 h of walking following 1 h in a supine position) and to exogenous A II injection (A II: 10 ng/kg/min intravenous infusion for 30 min). The 24-h urine sodium concentration was significantly lower in AN patients before therapy than after therapy. Plasma aldosterone secretory response to A II was significantly higher in AN patients before therapy in both postural change and exogenous A II injection tests compared with after therapy response and that of controls. On the other hand, there was no significant difference in adrenal response to postural change or to exogenous A II between AN patients after therapy and controls. In conclusion, increased A II sensitivity caused by chronic sodium deficiency in AN patients normalized over time as the patients recovered.

Alopecia universalis is a refractory condition. Although the cause of this disease is unknown, immunologic abnormalities have recently been suspected. Thus, we treated six cases of refractory alopecia universalis with immunotherapy. Oral administration of cyclosporine A (2.5 mg/kg) and prednisolone (5 mg/day) resulted in marked symptomatic improvement. Cyclosporine A did not produce any side effects because the administered dosage was relatively low. At present, more than 6 months after the cessation of treatment, recurrence of alopecia has not been seen. Oral administration of low-dose cyclosporine A and prednisolone is considered to be an effective treatment for this disease. Immunologic examination of peripheral blood demonstrated improvement of immunologic function. In particular, CD8-positive T cells, NK cells, and C3, which had been reduced, were increased. A reduction in active CD4 cells, eosinophils, and circulating immune complexes was observed. Histology with fluorescent antibodies showed T-cell infiltration around the hair matrixes. This phenomenon was no longer observed after treatment. These improvements in immunologic function were seen in parallel with the resolution of the clinical symptoms, indicating that immunologic abnormalities are related to this disease.

In anorexia nervosa (AN), abnormalities are present in the hypothalamic-pituitary-adrenal axis, but the prolactin (PRL) response to dexamethasone suppression test (DST) has not yet been studied. In order to study the interrelationships between the various endocrine abnormalities, we investigated the responses of PRL and cortisol to DST (1 mg of dexamethasone at 2300) in AN patients. The subjects were 12 female inpatients with AN and 8 age- and sex-matched healthy controls. The percentage suppression and absolute change in PRL levels before and after dexamethasone administration were significantly different in the 2 groups. In the control group PRL levels suppressed to 36.5 +/- 3.7% of basal, while AN levels declined to 79.4 +/- 8.9% of basal. When the percentage suppression of PRL was compared between patients with and without cortisol suppression, the mean PRL level was 68.9 +/- 7.8% of the basal level for the cortisol-suppressed patients and 100.4 +/- 19.1% for the nonsuppressed patients. Hence in both groups, the percentage PRL suppression was significantly reduced compared with the control group, and indeed nonexistent in cortisol-nonsuppressed patients. The finding that there was less PRL suppression in the cortisol-suppressed patients than in the controls suggests that, in AN, there may be an abnormality in PRL secretion not related to the hypothalamic-pituitary-adrenal axis. Further work is needed to distinguish between the PRL response to stress and potential hypothalamic abnormality.

The cover picture shows a red-luminescent EuIII complex with a tandem-connected tridentate phosphane oxide ligand. The coordination geometries of EuIII complexes with tridentate phosphane oxides provide characteristic distorted, capped square-antiprism structures with nine coordinating oxygen atoms. EuIII complexes with tridentate phosphane oxides offer relatively high emission quantum yields as a result of their low-symmetric and low-vibrational frequency structures. The characteristic structures and photophysical properties of polyhedral f-block metal complexes, nine-coordinate EuIII complexes with tridentate phosphane oxides, are demonstrated for the first time. Details are discussed in the article by Y. Hasegawa, T. Kawai et al. on p. 4777 ff.

Two cases of gastrin releasing peptide (GRP)-producing medullary thyroid carcinoma are presented. Immunohistochemical examination revealed the presence of GRP-like immunoreactivity (IR-GRP) in the primary tumor tissues. High concentration of IR-GRP was also demonstrated in extracts of the primary tumors by radioimmunologic means with use of a GRP-specific antiserum. Chromatographic analysis showed that the immunoreactivity was composed of at least two molecular forms: one behaved as synthetic porcine GRP on Sephadex G-50 gel filtration and the other as porcine GRP (14-27), a C-terminal active fragment of GRP. The IR-GRP was shown not to be attributed to bombesin-like immunoreactivity. Substance P-like immunoreactivity was not detected in the tumor tissues by either immunohistochemical or radioimmunologic means. This is, as far as the authors are aware, the first finding of IR-GRP as an ectopic product in medullary carcinoma.

A one-mg oral overnight dexamethasone suppression test (DST) was conducted on 22 inpatients with eating disorders. To confirm that the dexamethasone tablets had been ingested, we measured the plasma concentrations of dexamethasone the next morning (at 0900 hr after DST). The diagnosis of anorexia nervosa and bulimia was made according to the criteria for DSM-III, respectively. Of the 22 patients with eating disorders, 16 satisfied the criteria for anorexia nervosa and 6 for bulimia. The DST was carried out within 2 weeks of hospitalization on each patient. The subjects were given 1 mg of dexamethasone in the evening (at 2300 hr) and blood samples were collected the following day (at 0900, 1600 and 2100 hr, respectively). The plasma cortisol and dexamethasone levels were concurrently determined by RIA. The criterion for non-suppression was a failure to suppress the plasma cortisol levels below 5.0 micrograms/dl in any one of the three samples. All but one patient with bulimia had ingested the dexamethasone. Thirteen (62%) of 21 patients with eating disorders were nonsuppressors. We found a significant positive correlation between the plasma cortisol levels at 1600 hr or 2100 hr and a decrease in ideal body weight (n = 16, r = 0.613, p less than 0.05; r = 0.75, p less than 0.01, respectively) and a significant inverse relationship between the plasma dexamethasone levels at 0900 hr and the plasma cortisol levels at 1600 hr was recognized (n = 21, r = 0.631, p less than 0.01). These results suggest that the blood dexamethasone levels as well as body weight might contribute to the abnormalities of DST seen in patients with eating disorders.

Although prolactin (PRL) responses to thyrotropin-releasing hormone (TRH) have been described by many investigators, PRL secretion after insulin stimulation has rarely been documented in patients with anorexia nervosa (AN). We investigated PRL responses to TRH (500 micrograms) and insulin (0.1 U/kg) in 19 women with AN and 10 normal women. Levels of PRL stimulation at 60 min and later following insulin administration were significantly lower in AN than in normal women. PRL increased by at least 10 micrograms/ml after insulin in 42% of women with AN and in 70% of normal women. The maximum PRL increase (max delta PRL) did not differ after the two stimulations in the normal women. However, in AN, the max delta PRL after insulin stimulation (17.2 +/- 4.0 micrograms/l, mean +/- SEM) was significantly lower than that after TRH (49.1 +/- 6.4 micrograms/l). These findings suggest that anorectic women may have a disturbance in hypothalamic functions. Insulin-induced hypoglycemia is useful to determine the integrity of the hypothalamic-pituitary axis for PRL secretion, in combination with TRH stimulation.