bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinetic Coupling of Formaldehyde Oxidation and Oxide Formation on a Platinum Electrode
Authors: Nakabayashi Seiichiro , Tamura Kazuhisa , Uosaki Kohei 
Published: August 2005

Abstract
The reflectivity of a p-polarized laser beam on a polycrystalline platinum electrode is sensitive to the formation and reduction of the surface oxide. The derivative of this reflectivity is proportional to the current for the oxide formation and reduction. The reflectivity indicates the partial current for the oxide formation and reduction, which is hidden in the total current, including the 4-electron oxidation of formaldehyde. The time course of the reflectivity by a potential-step perturbation shows that formaldehyde makes the rate of the oxide formation and the reduction drastically asymmetric due to dissociative adsorption on the oxide-free platinum-electrode surface.
Synthesis and Properties of 9-(Tropylidenehydrazono)fluorene and Related Compounds
Authors: Minabe Masahiro , Nozawa Toshiya , Kurose Tomoko , Kimura Takao , Tsubota Motohiro 
Published: August 2005

Abstract
9-(Tropylidenehydrazono)fluorene (1) was obtained by a reaction between 9-fluorenone hydrazone and tropylium tetrafluoroborate, accompanied by 9-fluorenone azine, 9-(benzylidenehydrazono)fluorene, and 9,9-ditropylfluorene. The amination of 1 occurred at the 2-position of the tropylidene moiety. The addition of tosyl isocyanate to 1 gave the [8 + 2] cycloadduct at the 2,4,6-cycloheptatrien-1-imine structure.
Design and Synthesis of Peptides Passing through the Blood-Brain Barrier
Authors: Wakamiya Tateaki , Kamata Makoto , Kusumoto Shoichi , Kobayashi Hiroyuki , Sai Yoshimichi , Tamai Ikumi , Tsuji Akira 
Published: August 2005

Abstract
The blood-brain barrier (BBB) is a highly selective membranous barrier regulating the transport of substances in blood into the brain parenchyma. At present, delivery of biologically active peptides or peptide drugs into the brain is quite an important subject from the standpoint of chemotherapy for brain diseases. H–MeTyr–Arg–MeArg–d-Leu–NH(CH2)8NH2 termed 001-C8 was first synthesized to elucidate the structural specificity of peptides for passing through the BBB. The Nα-methylamino acid and d-amino acid residues were appropriately situated in this peptide to protect against the digestion by peptidase. Furthermore, a number of basic peptides were prepared as 001-C8 analogs for studying the relationship between structure and BBB permeability of peptides.
The Salt-Induced Sphere–Rod Transition of Micelles of 1-Tetradecylpyridinium Bromide in Aqueous NaBr Solutions
Authors: Fujio Katsuhiko 
Published: August 2005

Abstract
Static light scattering from aqueous NaBr solutions of 1-tetradecylpyridinium bromide (TPB) has been measured over the range of NaBr concentrations from 0 to 0.50 mol dm−3 at 25 °C, and the micelle molecular weight has been estimated. For 0—0.20 mol dm−3 NaBr, the reduced intensity of scattered light does not show any angular dependence, and the molecular weight of the spherical micelle of TPB slightly increases from 27.6 × 103 to 41.4 × 103 with increasing NaBr concentration. Beyond 0.20 mol dm−3 NaBr, the angular dissymmetry of the reduced scattering intensity and a steep increase in the micelle molecular weight from 41.4 × 103 to 177.8 × 103 are observed. Therefore, TPB has been considered to form rodlike micelles. The linear double logarithmic relationship between molecular weight and ionic strength holds for spherical and rodlike micelles, respectively. From the intersection of these two lines, the threshold NaBr concentration for the sphere-rod trainsition of TPB micelle is estimated to be 0.19 mol dm−3, where the micelle has a molecular weight of 41.3 × 103.
The Micellar Parameters of α,ω-Alkanediammonium Bis(decyl sulfate) Solutions and Their Mixtures
Authors: Satake Iwao , Kamikado Junichiro , Yasuda Youji , Maeda Tamaki , Hayakawa Katumitu 
Published: August 2005

Abstract
Conductometric and fluorescence probe investigations were carried in order to elucidate the micellar parameters of α,ω-alkanediammonium bis(decyl sulfate) with carbon-chain lengths (n) from 4 to 8 and their mixtures. In single surfactant systems, an increase in n was accompanied by a regular decrease in the critical micelle concentration (cmc) and a rapid increase in the micelle aggregation number (m), while the binding degree of the counter ion head group remained virtually constant at 0.90. The transfer free energy per methylene group of the counter ion from aqueous to micellar environments varied with increasing n from −0.35 kT to −0.68 kT. This fact suggests that the hydrocarbon chain of the counter ion, even with n = 4, can participate in the weak hydrophobic interaction with the micellar interior. In mixed solutions of n = 4 and 6, and n = 4 and 8, the cmc vs. y (mole fraction of n = 4) curves can be well interpreted in terms of the ideal mixing model. In both systems, the value of m gradually increases with increasing y. The fluorescence probe experiments indicate that the local environment around the solubilized pyrene in the mixed micelle resembles one another, regardless of y.
Surface Species Produced by the Reaction between Methane and Oxygen Radical Anion O·− on MgO at 298 K
Authors: Goto Akio , Aika Ken-ichi 
Published: August 2005

Abstract
The reaction between gaseous CH4 and surface O·− on MgO was studied at 298 K. The surface O·− was formed through a reaction of N2O with electrons trapped on MgO and examined with EPR. One mole of surface O·− determined by EPR was found to react with one mole of CH4 determined by GC. The resultant surface species were observed by an FT-IR and were identified to be methoxide and weakly absorbed methanol. The adsorbed methanol was produced by the reaction of methyl radicals (the initial product) with the surface hydroxy groups. Both products (methoxide and methanol) are found to be decomposed to CO and H2 at the elevated temperature such as 773 K.
Central Dogma for a Molecular Design Based on DNA: DNB (Databasing/Designable Nanobio) → ENB (Engineering Nanobio) → FNB (Functional Nanobio)
Authors: Nakano Shu-ichi , Sugimoto Naoki 
Published: August 2005

Abstract
Nanobiomaterials have become of broader interest over the past few years. In this review, we demonstrate functional biomolecules that we have constructed based on the biophysical data on nucleotides. We propose three concepts for the development of new nanobiomaterials; DNB (Databasing or Designable Nanobio) is the process of storing the biomolecular properties, ENB (Engineering Nanobio) is the process of conversion of the biomolecular properties to a molecular design, and FNB (Functional Nanobio) is the process of constructing functional molecules based on DNA technologies. Our approach of DNB → ENB → FNB can be the central dogma for a molecular design.
Synthesis and Characterization of Novel Iridium Complexes with Ligands of 2-Phenylimidazo[1,2-a]pyridine Derivatives and Application to Organic Light-emitting Diode
Authors: Takizawa Shin-ya , Nishida Jun-ichi , Tsuzuki Toshimitsu , Tokito Shizuo , Yamashita Yoshiro 
Published: August 2005

Abstract
Novel iridium complexes with ligands of 2-phenylimidazo[1,2-a]pyridines were prepared, and the emission maxima were found to be unusually dependent on the substituents on the phenyl ring. An OLED using the derivative was fabricated to show white emission.
X-ray Analysis of Bond Elongation in VO(acac)2 at the Excited State
Authors: Hoshino Manabu , Sekine Akiko , Uekusa Hidehiro , Ohashi Yuji 
Published: August 2005

Abstract
X-ray crystal structural analysis of bis(acetylacetonato) oxovanadium(IV), VO(acac)2, complex with photoirradiation at low temperatures clearly indicated the structural distortion caused by the production of the excited molecules with the elongated V=O and V–O bonds in the crystalline lattice.
Cross-section measurements for (n, 2n) and (n, p) reactions on platinum isotopes in the neutron energy range of 13.5 to 14.6 MeV
Authors: Luo Junhua , He Guozhu , Liu Zhongjie , Kong Xiangzhong 
Published: August 2005

Abstract
Cross-sections for (n,2n) and (n,p) reactions have been measured on platinum isotopes at the neutron energies of 13.5 to 14.6 MeV using the activation technique. Data are reported for the following reactions: 198Pt(n,2n)197m+gPt, 198Pt(n,2n)197mPt, 192Pt(n,2n) 191Pt, 190Pt(n,2n) 189Pt, 196Pt(n,2n)195mPt+195Pt(n,n
′)195mPt, 194Pt (n,p) 194Ir, 195Pt(n,p)195mIr and 196Pt(n,p)196mIr. The neutron fluences were determined using the monitor reaction 93Nb(n,2n)92mNb or 27Al(n,α) 24Na.
The solubility product of NaUO2PO4·xH2O determined in phosphate and carbonate solutions
Authors: Felmy Andrew R. , Xia Yuanxian , Wang Zheming 
Published: August 2005

Abstract
The solubility product of NaUO2PO4· x H2O was determined in phosphate containing solutions at low pCH+ values in the absence of carbonate and at higher pCH+ values in the presence of carbonate. NaUO2PO4· x H2O exhibited very low solubilities (∼10−7 M in U) over a broad range of hydrogen ion concentrations, NaNO3 concentrations and in the absence of added carbonate. Time Resolved Laser Fluorescence Spectroscopy (TRLFS) analysis of non-carbonate solutions outside of the acidic region revealed the presence of complex mixtures of aqueous U(VI) hydroxyl or phosphate species and uranium phosphate nanoparticles. The presence of the nanoparticles made it impossible to accurately calculate a solubility product for NaUO2PO4· x H2O in the absence of carbonate and at higher pCH+ values. Therefore in order to increase the concentration of U(VI) in solution and thereby verify the solubility product calculated from the most acidic samples, we systematically introduced know concentrations of carbonate, which resulted in the formation of U(VI) carbonate complexes. Development of an accurate aqueous thermodynamic model for the aqueous U(VI) carbonate complexes then allowed calculation of a solubility product for NaUO2PO4· x H2O in the higher pH samples which was in good agreement with the values for the more acidic samples.
Speciation of technetium(IV) chloride under gamma irradiation
Authors: Fattahi M. , Vichot L. , Poineau F. , Houée-Levin C. , Grambow B. 
Published: August 2005

AbstractSpeciation of Tc in aqueous solution is a complex phenomenon because several parameters intervene simultaneously. We show under gamma radiations, it is completely modified. At pH 8.5 TcO2is oxidized to Tc(VII) with a yield of 1.38×10−7mol J−1. At pH 1.5, it was demonstrated that Tc is present as hydroxylated species TcnOy(4n-2y)+(L. Vichot, M. Fattahi, M. Musikas: Radiochim. Acta 91, 263 (2003)). Its oxidation leads also to Tc(VII) with an experimental yield of 1.45×10−7mol J−1. In more acidic solutions, results are consistent with hydrolysis and oxidation of Tc(IV) to Tc(V). As for colloidal solutions of Tc(IV) or TcO2, they give Tc(VII) whereas solutions of TcCl62-at pH 0.5 and 1.5 do not lead directly to Tc(VII). Reduced states of Tc are very sensitive to radiation. Hydrolysis as well as polymerisation of Tc are accelerated. Furthermore the radiolytic processes are pH dependent.
Zirconium decontamination from aqueous media using lateritic minerals
Authors: Khalid Nasir , Daud Muhammad , Ahmad Shujaat 
Published: August 2005

Abstract
The sorption behavior of zirconium on minerals from a lateritic weathering has been carried out to evaluate its potential for the decontamination of zirconium ions from aqueous solutions. Various physico-chemical parameters such as selection of appropriate electrolyte, equilibration time, amount of adsorbent, concentration of adsorbate, effect of diverse ions and temperature were studied in order to simulate the best conditions under which this material can be used as an adsorbent, employing batch method and radiotracer technique. Maximum adsorption was observed at 0.005 mol L−1 acid solutions (HNO3, HCl, H2SO4 and HClO4) using 0.3 g of adsorbent for 1.499×10−4 mol L−1 zirconium concentration in five minutes equilibration time. Studies show that the adsorption of zirconium decreases with the increase in the concentrations of all the acids. The adsorption data follows the Freundlich isotherm over the range of 7.5×10−5 to 3.0×10−3 mol L−1 zirconium concentration. The characteristic Freundlich constants i.e. 1/n = 0.55±0.03 and K=1.36×10−3±7.0×10−5 mol g−1 have been computed for the sorption system. The sorption mean free energy from the Dubinin–Radushkevich isotherm is 11.2±0.4 kJ mol−1 indicating ion-exchange mechanism of chemisorption. The uptake of zirconium increases with the rise in temperature (283-323 K). Thermodynamic quantities i.e. ΔG, ΔS and ΔH have also been calculated for the system. The sorption process was found endothermic.
The effects of thyroid hormones on circulating markers of cell-mediated immune response, as studied in patients with differentiated thyroid carcinoma before and during thyroxine withdrawal
Authors: Botella-Carretero José I , Prados Aranzazu , Manzano Luis , Montero María T , Escribano Luis , Sancho José , Escobar-Morreale Héctor F 
Published: August 2005

Objective: To address the influence of thyroid hormones on circulating markers of cell-mediated immune response in anin vivohuman model.Subjects and design: Twenty-two patients with stage I differentiated thyroid carcinoma were studied on the last day of thyroxine suppressive treatment, 4–7 days after withdrawal, and the day before whole body scanning. Three patients were excluded because of residual disease. Twenty euthyroid individuals served as controls. Serum thyrotrophin and thyroid hormones were measured by an immunometric assay, circulating cytokines by enzyme-linked immuno-sorbent assay and lymphoid populations by flow cytometry.Results: Thyroid function in patients changed from subclinical or mild hyperthyroidism at the first visit, to a situation of normal circulating levels of free thyroxine and triiodothyronine at the second, ending in a state of overt hypothyroidism. Thyroxine suppressive treatment in patients increased serum interleukin-18 concentrations (IL-18, mean±s.d., 280±122 vs 183±106 pg/ml, F = 3.192,P= 0.029), soluble interleukin-2 receptor levels (sIL-2R, 4368±1480 vs 2564±846 pg/ml, F = 21.324,P< 0.001), and the percentage of natural killer (NK) cells in peripheral blood (15.9±8.6 vs 10.5±3.6%, F = 4.977,P= 0.004) compared with controls. After thyroxine withdrawal, serum levels of IL-18, sIL-2R and the percentage of NK cells decreased progressively.Conclusion: Our present results suggest that thyroid hormones modulate the cell-mediated immune response in humans.
Expression of renal 11β-hydroxysteroid dehydrogenase type 2 is decreased in patients with impaired renal function
Authors: Quinkler Marcus , Zehnder Daniel , Lepenies Julia , Petrelli Massimiliano D , Moore Jasbir S , Hughes Susan V , Cockwell Paul , Hewison Martin , Stewart Paul M 
Published: August 2005

Objective: Renal 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) enables selective access of aldosterone to the mineralocorticoid receptor (MR). Impaired 11β-HSD2 activity has been suggested in patients with hypertension as well as in patients with renal disease, where it may contribute to sodium retention, oedema and hypertension. To date, these studies have relied upon urinary cortisol (F) metabolite levels as surrogate markers of renal 11β-HSD2 activity.Methods: We have directly analysed renal 11β-HSD2 mRNA expression in 95 patients undergoing kidney biopsy using TaqMan real-time PCR. Serum and 24-h urine samples were used to document underlying renal function and endocrine parameters. Urinary F and cortisone (E) metabolites were analysed using gas chromatography/mass spectrometry.Results: Expression of 11β-HSD2 did not correlate with blood pressure or urinary Na/K ratio, but a significant positive correlation with creatinine clearance was observed (r= 0.284;P< 0.01). Immunofluorescence and confocal laser microscopy confirmed decreased 11β-HSD2 expression in patients with impaired renal function. For the first time, we showed that 11β-HSD2 mRNA expression correlated negatively with the urinary free (UF) F/E (UFF/UFE) ratio (r= 0.276;P< 0.05) as well as with the urinary tetrahydrocortisol + 5α-tetrahydrocortisol/tetrahydrocortisone ((THF + αTHF)/THE) ratio (r= 0.256;P< 0.05). No difference in 11β-HSD2 mRNA expression or in the UFF/UFE ratio was found between groups with no proteinuria, microalbuminuria, moderate or severe proteinuria. In contrast, the urinary (THF + αTHF)/THE ratio increased significantly (P< 0.05) in patients with severe albuminuria, suggesting increased hepatic 11β-HSD1 in those patients.Conclusions: These data suggest that renal 11β-HSD2 expression may be represented only marginally better, if at all, by the UFF/UFE than by the (THF + αTHF)/THE ratio. Reduced renal 11β-HSD2 expression may lead to occupancy of the MR by glucocorticoids such as cortisol and may contribute to the increased sodium retention seen in patients with impaired renal function.
Pegvisomant therapy in pituitary gigantism: successful treatment in a 12-year-old girl
Authors: Rix M , Laurberg P , Hoejberg A S , Brock-Jacobsen B 
Published: August 2005

Objective: The use of a growth hormone (GH) receptor antagonist, pegvisomant has shown great promise in adults with acromegaly, but experience in paediatric patients is lacking. We aimed to describe the results of pegvisomant therapy in a 12-year-old girl with an aggressive GH-secreting pituitary tumour.Design: To evaluate the ability of pegvisomant therapy to control the effects of peripheral GH excess in a case of pituitary gigantism.Methods: Pegvisomant was introduced at 10 mg/day, given subcutaneously, and gradually increased to 20 mg/day until serum IGF-I was normal for age.Results: A large pituitary adenoma with suprasellar extension was diagnosed in a 12-year-old girl with progressive tall stature (178 cm), GH hypersecretion without suppression during oral glucose loading (nadir serum GH, 90 mU/l), high serum IGF-I and serum prolactin levels. Surgical extirpation was not possible because tumour tissue was fibrous and adherent to the optical nerves. Histological examination showed a mixed GH- and prolactin-secreting adenoma with lymphocytic infiltration of B and T cells. Treatment with a dopamine agonist, cabergoline, normalized serum prolactin, but GH secretion was resistant to both somatostatin analogue, octreotide and cabergoline. Radiation followed by pegvisomant therapy titrated up in dose to 20 mg/day led to a marked reduction in GH secretion and normalization of IGF-I, and to growth arrest and improvement of well-being.Conclusions: We suggest that treatment in pituitary gigantism with pegvisomant is safe and may normalize IGF-I levels and effectively stop growing.
Machine learning approaches for phenotype–genotype mapping: predicting heterozygous mutations in the CYP21B gene from steroid profiles
Authors: Prank Klaus , Schulze Egbert , Eckert Olaf , Nattkemper Tim W , Bettendorf Markus , Maser-Gluth Christiane , Sejnowski Terrence J , Grote Arno , Penner Erika , von zur Mühlen Alexander , Brabant Georg 
Published: August 2005

Objective: Non-linear relations between multiple biochemical parameters are the basis for the diagnosis of many diseases. Traditional linear analytical methods are not reliable predictors. Novel nonlinear techniques are increasingly used to improve the diagnostic accuracy of automated data interpretation. This has been exemplified in particular for the classification and diagnostic prediction of cancers based on expression profiling data. Our objective was to predict the genotype from complex biochemical data by comparing the performance of experienced clinicians to traditional linear analysis, and to novel non-linear analytical methods.
Design and methods: As a model, we used a well-defined set of interconnected data consisting of unstimulated serum levels of steroid intermediates assessed in 54 subjects heterozygous for a mutation of the 21-hydroxylase gene (CYP21B) and in 43 healthy controls.
Results: The genetic alteration was predicted from the pattern of steroid levels with an accuracy of 39% by clinicians and of 64% by linear analysis. In contrast, non-linear analysis, such as self-organizing artificial neural networks, support vector machines, and nearest neighbour classifiers, allowed for higher accuracy up to 83%.
Conclusions: The successful application of these non-linear adaptive methods to capture specific biochemical problems may have generalized implications for biochemical testing in many areas. Nonlinear analytical techniques such as neural networks, support vector machines, and nearest neighbour classifiers may serve as an important adjunct to the decision process of a human investigator not ‘trained’ in a specific complex clinical or laboratory setting and may aid them to classify the problem more directly.
Corticotroph adenoma of the pituitary in a patient with X-linked adrenal hypoplasia congenita due to a novel mutation of the DAX-1 gene
Authors: De Menis Ernesto , Roncaroli Federico , Calvari Vladimiro , Chiarini Valerio , Pauletto Paolo , Camerino Giovanna , Cremonini Nadia 
Published: August 2005

Objective: Mutations in the DAX-1 gene result in X-linked congenital adrenal hypoplasia. The classic clinical presentation is primary adrenal insufficiency in early life and hypogonadotropic hypogonadism at the time of expected puberty, but recent data have expanded the phenotypic spectrum of DAX-1 mutations. We report the occurrence of an ACTH-secreting adenoma in a patient with X-linked congenital adrenal hypoplasia.
Design and methods: Detailed clinical, radiological and pathological investigation of the pituitary adenoma. Genomic analysis of the DAX-1 gene in the patient and his mother.
Results: In this patient, primary adrenal failure had been diagnosed at 3 years of age and, despite replacement therapy, at 30 years of age progressive pigmentation developed and impairment of the visual field followed. ACTH was 24 980 pg/ml and nuclear magnetic resonance disclosed a huge pituitary adenoma. Three transsphenoidal operations and radiotherapy were necessary to remove the tumor mass and control ACTH secretion. Histologically, the adenoma was composed of chromophobic and basophilic neoplastic cells with positive immunostaining for ACTH. Moreover, a novel mutation was found both in the patient and his mother: a 4 bp insertion (AGCG) at nucleotide 259, in exon 1 resulting in a frame shift and premature termination.
Conclusions: This case suggests that in adrenal hypoplasia congenita the development of a pituitary adenoma should be considered when a sudden rise of ACTH occurs despite adequate steroid substitution.