bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of (R)‐ and (S)‐[O‐methyl‐11C]N‐[2‐[3‐(2‐cyano‐phenoxy)‐2‐hydroxy‐propylamino]‐ethyl]‐N′‐(4‐methoxy‐phenyl)‐urea as candidate high affinity β1‐adrenoceptor PET radioligands
Authors: Wagner Stefan , Law Marilyn P. , Riemann Burkhard , Pike Victor W. , Breyholz Hans‐Jörg , Höltke Carsten , Faust Andreas , Schober Otmar , Schäfers Michael , Kopka Klaus 
Published: June 2005

AbstractMolecular imaging and quantification of myocardial β1‐adrenoceptor (AR) rather than total β‐AR density is of great clinical interest since cardiac biopsy studies suggest that myocardial β1‐AR density is reduced in patients with chronic heart failure whereas cardiac β2‐AR density may vary. Positron emission tomography (PET), with appropriate radioligands, offers the possibility to assess β‐AR density non‐invasively in humans. However, no PET radioligand for the selective imaging of cardiac β1‐ARs is clinically available. Here some derivatives of the well characterized β1‐AR selective antagonist, ICI 89,406, namely the enantiomers of N‐[2‐[3‐(2‐cyano‐phenoxy)‐2‐hydroxy‐propylamino]‐ethyl]‐N′‐(4‐hydroxy‐phenyl)‐urea (5a and 5b) were synthesized and evaluated in vitro. The (R)‐isomer 5a was more β1‐selective but has lower affinity than its (S)‐enantiomer 5b (β1‐AR selectivity: 6100 vs 1240; β1‐affinity: K1 = 0.288 nM vs K1 = 0.067 nM). Etherification of the analogous desmethyl precursors, 5e and 5f, respectively, with [11C]iodomethane gave 11C‐labelled versions of 5a and 5b, namely 5g and 5h, in 44 ± 5% radiochemical yield (decay‐corrected) and 97.4 ± 1.3% radiochemical purity with specific radioactivities of 26.4 ± 9.4 GBq/µmol within 41.2 ± 3.4 min from the end of bombardment (n = 14). 5g and 5h are now being evaluated as candidate radioligands for myocardial β1‐ARs. Copyright © 2005 John Wiley & Sons, Ltd.
On the decay of solutions for a class of quasilinear hyperbolic equations with non‐linear damping and source terms
Authors: Messaoudi Salim A. 
Published: June 2005

AbstractIn this paper, we consider the non‐linear wave equation

a,b>0, associated with initial and Dirichlet boundary conditions. Under suitable conditions on α, m, and p, we give precise decay rates for the solution. In particular, we show that for m=0, the decay is exponential. This work improves the result by Yang (Math. Meth. Appl. Sci. 2002; 25:795–814). Copyright © 2005 John Wiley & Sons, Ltd.
Rheological, mechanical and morphological properties of thermoplastic vulcanizates based on NR‐g‐PMMA/PMMA blends
Authors: Nakason C. , Pechurai W. , Sahakaro K. , Kaesaman A. 
Published: June 2005

AbstractGraft copolymer of natural rubber and poly(methyl methacrylate) (NR‐g‐PMMA) was prepared using semi‐batch emulsion polymerization technique via bipolar redox initiation system. It was found that the grafted PMMA increased with the increase of methyl methacrylate (MMA) concentration used in the graft copolymerization. The NR‐g‐PMMA was later used to prepare thermoplastic vulcanizates (TPVs) by blending with PMMA through dynamic vulcanization technique. Conventional vulcanization (CV) and efficient sulphur vulcanization (EV) systems were studied. It was found that the CV system provided polymer melt with lower shear stress and viscosity at a given shear rate. This causes ease of processability of the TPVs via extrusion and injection molding processes. Furthermore, the TPVs with the CV system showed higher ultimate tensile strength and elongation. The results correspond to the morphological properties of the TPVs. That is, finer dispersion of the small vulcanized rubber particles were observed in the PMMA matrix. Various blend ratios of the NR‐g‐PMMA/PMMA blends using various types of NR‐g‐PMMA (i.e. prepared using various percentage molar ratios of NR and MMA) were later studied via dynamic vulcanization by a conventional sulphur vulcanization system. It was found that increasing the level of PMMA caused increasing trend of the tensile strength and hardness properties but decreasing level of elongation properties. Increasing level of the grafted PMMA in NR molecules showed the same trend of mechanical properties as in the case of increasing concentration of PMMA used as a blend component. From morphological studies, two phase morphologies were observed with a continuous PMMA phase and dispersed elastomeric phase. It was also found that more finely dispersed elastomeric phase was obtained with increasing the grafted PMMA in the NR molecules. Copyright © 2005 John Wiley & Sons, Ltd.
Reciprocal changes in trefoil 1 and 2 expression in stomachs of mice with gastric unit hypertrophy and inflammation
Authors: Franic TV , van Driel IR , Gleeson PA , Giraud AS , Judd LM 
Published: June 2005

AbstractH+/K+‐ATPase β‐subunit‐deficient mice (129/Sv background) display numerous pathologies in the stomach. Expression of the mutation in BALB/cCrSlc mice results in the development of an aberrant ‘mucus‐rich’ cell population. ‘Mucus‐rich’ cells have been described in stomachs of mice with autoimmune gastritis, a disease mediated by CD4+ T cells. Other pathological features of autoimmune gastritis are similar to those in H+/K+ β‐deficient mice and include a mononuclear cell infiltrate in the gastric mucosa, non‐functional or absent parietal cells, depletion of zymogenic cells, hypergastrinaemia, and gastric unit hypertrophy caused by immature cell hyperplasia. The present study investigates further the aberrant gastric ‘mucus‐rich’ cell lineage and analyses the mRNA expression of mucus cell products TFF1 and TFF2. ‘Mucus‐rich’ cells stained for both acidic and neutral mucins, and with a TFF2‐specific antibody. Stomachs from both models expressed decreased TFF1 mRNA and reciprocally increased TFF2 mRNA. The involvement of gastrin in regulating trefoil mRNA expression was also investigated using gastrin‐deficient mice. In contrast to previous findings, gastrin did not positively regulate TFF1 mRNA expression, but there was possible augmentation of TFF2. Additionally, a clear role for inflammation was established involving both polymorphonuclear and mononuclear cells in these models, and a link was found between mucosal hypertrophy and increased interleukin‐11 (IL‐11) expression. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Electron paramagnetic resonance spin probe study of carbon dioxide‐induced polymer plasticization
Authors: Harbron Elizabeth J. , Bunyard W. Clayton , Forbes Malcolm D. E. 
Published: June 2005

AbstractSteady‐state electron paramagnetic resonance (EPR) spectroscopy using nitroxide spin probes has been used to investigate the plasticization of poly(vinyl acetate) and poly(ethyl methacrylate) by carbon dioxide. By varying the CO2 pressure at constant ambient temperature, the glass transition for each polymer could be depressed to 25 °C. This effect has been quantified by a parameter P50G, obtained by plotting the EPR spectral width as a function of CO2 pressure. Certain spin probes showed free volume distribution effects, manifested in the EPR spectra as “double peaks.” Possible reasons for this phenomenon are presented and discussed, and the efficacy of CO2 as a plasticizer is clearly demonstrated by direct comparison with di‐n‐butyl phthalate. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2097–2108, 2005
Molecular structure development of metallocene‐catalyzed linear low density polyethylene under ultrasonic irradiation
Authors: Wu Hong , Guo Shaoyun , Li Zhen 
Published: June 2005

AbstractIn this work, the effect of ultrasonic irradiation on molecular structure development of metallocene‐catalyzed linear low density polyethylene (mLLDPE) was studied. GPC results show that ultrasonic irradiation have influence on molecular weight and molecular weight distribution of mLLDPE. Molecular weight of mLLDPE decreases slightly at the initial 30 s of ultrasonic irradiation and then increases obviously; its distribution becomes wider with the increase of ultrasonic irradiation time. The power and frequency of ultrasonic irradiation have the distinct influence on molecular weight and its distribution of mLLDPE. DSC results show that ultrasonic irradiation has distinct influence on multiple step crystallizing behaviors of mLLDPE because of the change of branched chain in mLLDPE molecules. Thermal stability of mLLDPE is improved greatly because of micro‐crosslinking structure in mLLDPE molecule, which is formed in the presence of ultrasonic irradiation. A possible mechanism for molecular structure development of mLLDPE in the presence of ultrasonic irradiation is also proposed in this paper. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2121–2129, 2005
Gain scheduled control for discrete‐time systems depending on bounded rate parameters
Authors: Amato Francesco , Mattei Massimiliano , Pironti Alfredo 
Published: June 2005

AbstractIn this paper we consider a linear, discrete‐time system depending multi‐affinely on uncertain, real time‐varying parameters. A new sufficient condition for the stability of this class of systems, in terms of a feasibility problem involving linear matrix inequalities (LMIs), is obtained under the hypothesis that a bound on the rate of variation of the parameters is known. This condition, obtained by the aid of parameter dependent Lyapunov functions, obviously turns out to be less restrictive than that one obtained via the classical quadratic stability (QS) approach, which guarantees stability in presence of arbitrary time‐varying parameters. An important point is that the methodology proposed in this paper may result in being less conservative than the classical QS approachevenin the absence of an explicit bound on the parameters rate of variation. Concerning the synthesis context, the design of a gain scheduled compensator based on the above approach is also proposed. It is shown that, if a suitable LMI problem is feasible, the solution of such problem allows to design an output feedback gain scheduled dynamic compensator in a controller‐observer form stabilizing the class of systems which is dealt with. The stability conditions are then extended to take into accountL2performance requirements. Some numerical examples are carried out to show the effectiveness and to investigate the computational burden required by the proposed approach. Copyright © 2005 John Wiley & Sons, Ltd.
Individual growth curve models for assessing evidence‐based referral criteria in growth monitoring
Authors: van Dommelen P. , van Buuren S. , Zandwijken G. R. J. , Verkerk P. H. 
Published: June 2005

AbstractThe goal of this study is to assess whether a growth curve model approach will lead to a more precise detection of Turner sydnrome (TS) than conventional referral criteria for growth monitoring. The Jenss–Bayley growth curve model was used to describe the process of growth over time. A new screening rule is defined on the parameters of this growth curve model, parental height and gestational age. The rule is applied to longitudinal growth data of a group of children with TS (n=777) and a reference (n=487) group. The outcome measures are sensitivity, specificity and median referral age. Growth curve parameters for TS children were different from reference children and can therefore be used for screening. The Jenss–Bayley growth model, which uses all longitudinal measurements from birth to a maximum age of 5 years with at least one measurement after the age of 2, together with parental height and gestational age can achieve a sensitivity of 85.2 per cent with a specificity of 99.5 per cent and a median referral age of 4.2 (the last measurement between the age of 2 and 5 of each child is considered to be the moment of referral). Sensitivity increases by 2 percentage points when decreasing the specificity to 99 per cent. The Jenss–Bayley growth model from birth to a maximum age of 8 years with at least one measurement after the age of 2, together with parental height results in a sensitivity of 89.0 per cent with a specificity of 99.5 per cent and a median referral age of 6.1. For a specificity of 98 per cent, we obtain a sensitivity of 92.3 per cent. In comparison to conventional rules applied to the same data, sensitivity is about 11–30 percentage points higher at the same level of specificity for the Jenss–Bayley growth rule. We conclude that from the age of 4, growth curve models can improve the screening on TS to conventional screening rules. Copyright © 2005 John Wiley & Sons, Ltd.
Disorders of the electron transport chain
Authors: Adams P. L. , Turnbull D. M. 
Published: June 2005

SummaryDefects in a pathway as complex as the electron transport chain cause a variety of clinical abnormalities, which vary from fatal lactic acidosis in infancy to mild muscle disease in adults. The primary defect may reside in the nucleus or the mitochondrial genome. Until relatively recently, biochemical assays were the definitive means of establishing a defect of the electron transport chain. However, identification of mtDNA abnormalities allows defects to be defined more precisely and in a number of cases provides an easier (more reliable) means of investigation. Despite advances in this field, disorders of the electron transport chain still remain underdiagnosed. This review attempts to provide a general outline of the biochemistry and molecular genetics associated with these disorders and some of the factors involved in establishing a diagnosis in those patients with a suspected defect of the electron transport chain.
Metabolic intermediates in lactic acidosis: compounds, samples and interpretation
Authors: Poggi‐Travert F. , Martin D. , Billette de Villemeur T. , Bonnefont J. P. , Vassault A. , Rabier D. , Charpentier C. , Kamoun P. , Munnich A. , Saudubray J. M. 
Published: June 2005

SummaryA number of acquired conditions including infections, severe catabolic states, tissue anoxia, severe dehydration and poisoning can give rise to hyperlactacidaemia. All these causes should be ruled out before considering inborn errors of metabolism. Carefully collected samples are necessary if artefacts that results in spuriously increased lactate/pyruvate (L/P) and 3‐hydroxybutyrate/acetoacetate (B/A) ratios are to be avoided. When properly performed, 24‐h studies of L/P and B/A ratios provide a useful tool in making a diagnosis. A few metabolic profiles when present are specific or highly suggestive of a given disorder. When the L/P ratio is normal or low, pyruvate dehydrogenase (PDH) deficiency is highly probable whatever the lactate concentration, which is often only moderately elevated after meal, may be. When the L/P ratio is very high in association with post‐prandial hyperketonaemia and in contrast to a normal or low B/A ratio, pyruvate carboxylase (PC) deficiency andα‐ketoglutarate dehydrogenase (KGDH) deficiency are the most likely diagnoses. The distinction between the two disorders relies upon amino acid and organic acid profiles (glutamate andα‐ketoglutarate accumulations in KGDH deficiency and hyperammonaemia and hypercitrullinaemia in PC deficiency). When both L/P and B/A ratios are elevated and associated with significant post‐prandial hyperketonaemia, respiratory‐chain disorders should first be suspected. All other profiles, especially a high L/P ratio without hyperketonaemia, are compatible with respiratory‐chain disorders but are not specific; all acquired anoxic conditions should also be ruled out. Clearly, the clinical utility of these profiles needs to be interpreted cautiously in very ill patients in relation to the cardiocirculatory condition and to therapy. Finally, a normal profile, even after stress and loading, does not rule out an inborn error of lactate/pyruvate oxidation.
Mitochondrial encephalomyopathies: what next?
Authors: DiMauro S. 
Published: June 2005

SummaryIn few areas of medicine has progress been more spectacular than in the field of mitochondrial diseases, especially those related to mtDNA mutations. Much remains to be done, however, and this brief review discusses the following areas of research where progress has been more limited or data are still controversial: (1) the molecular basis of respiratory‐chain defects due to nuclear DNA mutations; (2) defects of mitochondrial protein importation; (3) defects of intergenomic signalling; (4) pathophysiology of mtDNA‐related disorders; (5) ageing and age‐related neuro‐degenerative diseases; (6) therapy; and (7) genetic counselling.
Morphological studies of skeletal muscle in lactic acidosis
Authors: Romero N. B. , Lombès A. , Touati G. , Rigal O. , Frachon P. , Cheval M. A. , Giraud M. , Possekel S. , Fardeau M. , Ogier de Baulny H. 
Published: June 2005

SummaryThis paper underscores the contribution of routine morphological examination of skeletal muscle in patients with lactic acidosis. Mitochondrial disorders are by far the most common causes of primary lactic acidosis, in which muscle biopsy analysis helps in diagnosis and in the search for the molecular anomalies. Thus, we focus our attention on one particular point: the contribution of the morphological study of muscle biopsy in primary lactic acidosis due to mitochondrial disorders, especially mitochondrial respiratory‐chain diseases.
Magnetic resonance imaging in lactic acidosis
Authors: van der Knaap M. S. , Jakobs C. , Valk J. 
Published: June 2005

SummaryMitochondrial defects, defects in gluconeogenesis, and biotin‐responsive multiple carboxylase deficiency are disorders characterized by primary lactic acidosis. In this review, characteristic findings in magnetic resonance imaging (MRI) of the brain, as related to histopathological abnormalities, are described for the different disorders and the diagnostic value of the MRI findings is discussed. Inborn errors of metabolism with primary lactic acidosis should be considered in particular when MRI shows lesions similar to or reminiscent of effects of focal or generalized hypoxia‐ischaemia, or when MRI shows signs of chronic neurodegeneration, but rarely in cases with predominantly white‐matter changes.
Riboflavin‐responsive ethylmalonic—adipic aciduria
Authors: Green A. , Marshall T. G. , Bennett M. J. , Gray R. G. F. , Pollitt R. J. 
Published: June 2005

AbstractA patient presenting with a condition resembling Reye's syndrome was found to have a urinary organic acid excretion pattern similar to those previously described in a single patient with ethylmalonic‐adipic aciduria. The present patient responded clinically to riboflavin supplementation and his fibroblasts, when cultured in riboflavin‐depleted medium, showed an abnormal reduction in the rate of butyrate oxidation.
Heterogeneity and complementation analysis of fibroblasts from vitamin B6 responsive and non‐responsive patients with gyrate atrophy of the choroid and retina
Authors: Wirtz M. K. , Kennaway N. G. , Weleber R. G. 
Published: June 2005

AbstractFibroblasts from four pyridoxine responsive and three non‐responsive patients with gyrate atrophy of the choroid and retina have been examined. Responsive patients had higher activity of ornithine ketoacid transaminase (OKT) in cell homogenates and greater incorporation of radioactivity from14C‐ornithine into protein in cultured cellsin situ compared to non‐responsive patients. Complementation analysis of the cells from these seven patients was performed, based on the ratio of incorporation of14C/3H into protein in fused cells incubated in14C‐ornithine and3H‐leucine. Lack of positive complementation in these crosses suggests that pyridoxine responsive and non‐responsive patients with gyrate atrophy represent different allelic mutations of the same genetic locus coding for OKT.
Hypercholesterolaemia type II: Changes in plasma insulin and glucagon levels after portacaval shunt
Authors: Farriaux J. P. , Luyckx A. S. , Ribet M. 
Published: June 2005

AbstractInsulinaemia and glucagonaemia were measured in two cases of hypercholesterolaemia type II, before and after portacaval shunt. The results show an increase of both hormones although these variations are not concomitant with the decrease in cholesterolaemia. The data still do not explain the mechanism of the decrease.
Results of screening for phenylalanine and other amino acid disturbances among pregnant women
Authors: Hyánek J. , Homolka J. , Trnka J. , Seemanová E. , Červenka J. , Třesohlavá Z. , Kapras J. , Doležal A. , Šráček J. , Vácha V. , Hoza J. , Lošan F. , Nevšímalová S. , Malá M. , Viletová H. 
Published: June 2005

AbstractBlood specimens were collected from 15000 pregnant women during the first 3 months of their pregnancy and screened for amino acid disturbances by means of paper chromatography. A high incidence of disturbances in the phenylalanine metabolism was discovered: three cases of mild hyperphenylalaninaemia without phenylpyruvicaciduria (incidence 1:5000); two cases of mild hyperphenylalaninaemia with phenylpyruvicaciduria (incidence 1:7550); four cases of mild phenylketonuria (incidence 1:3750). Disturbances in the metabolism of other amino acids were found to be rare. Metabolic and genealogical findings in some detected families are briefly described.
Phenylketonuria in Indian children
Authors: Joshua Gertrude E. , Chandy S. , Radhakrishnan A. N. , Mammen D. , Mathai K. V. 
Published: June 2005

AbstractThree untreated phenylketonuric Indian children aged respectively 3 1/2 years, 1 1/2 years and 1 year showed rapid neurological deterioration. Plasma, cerebrospinal fluid and urine phenylalanine concentrations were significantly raised and the phenylalanine‐tyrosine ratio was high. Analysis of a biopsy of the right frontal lobe of the brain in one case showed the myeline lipids—cerebroside and sulphatide—to be decreased. The total cerebroside in white matter was low. Light microscopy showed marked pallor of the white matter of the brain and extensive spongy degeneration. Ultrastructurally these spongy vesicles are located between the lamellae of the myelin sheath.
Anderson‐fabry disease: Rapid detection of carriers by hair bulb analysis
Authors: Ejiofor A. , Robinson D. , Wise D. , Hamers M. , Tager J. M. 
Published: June 2005

AbstractA rapid and simple method is described for the identification of the carrier state in angiokeratoma corporis diffusum. The α‐galactosidase (α‐D‐galactoside galactohydrolase, E.C.3.2.1.22) activities in individual hair roots are measured and compared with those ofN‐acetyl‐β‐hexosaminidase (E.C.3.2.1.30), another lysosomal enzyme that is not affected. The cellular mosaicism typical of females heterozygous for X‐linked disorders is revealed by the presence of normal, affected and partially affected hair roots. Normal individuals show no affected roots, while males hemizygous for the trait have no hair roots with enzyme activities in the normal range.
Hypoxanthine‐guanine phosphoribosyltransferase deficiency in three brothers with gout: Characterization of a variant, HPRTEdinburgh, having altered isoelectric point, increased thermal lability and normal levels of messenger RNA
Authors: Snyder F. F. , Joyce J. E. , Carter‐Edwards T. , Joshi R. , Rylance H. L. , Wallace R. C. , Nuki G. 
Published: June 2005

SummaryThree brothers who developed acute gouty arthritis at ages 16, 20 and 26 years were found to have increased plasma urate. Erythrocyte hypoxanthine phosphoribosyltransferase (HPRT) activity was less than 1% of normal and adenine phosphoribosyltransferase (APRT) activity was increased 2–3‐fold. This variant, HPRTEdinburgh, was further studied using lymphoblast lines established from these patients and the following observations are consistent with a mutation involving a single amino acid substitution. Lymphoblasts from these patients had 0.9–1.6% of control HPRT activity which was 8‐fold more labile than control activity at 75°C. Isoelectric focusing of the variant protein in polyacrylamide gels indicated a pI of 6.5–6.7 which is more basic than normal HPRT, pI 6.0–6.3. The Michaelis constants were increased: 10‐fold for hypoxanthine from 1.3 to 13 µmol/L, and 5‐fold for PP‐ribose‐P from 6 to 30 µmol/L, for control and variant respectively. TheKi for product inhibition by GMP was marginally increased in the variant. Northern blot analysis of variant lymphoblast RNA indicated normal amounts of the expected 1.6 kilobase messenger RNA.