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Kinds of X Terms modified by X Selected AbstractsDi-2-pyridyl Ketone Oxime in Zinc Chemistry: Inverse 12-Metallacrown-4 Complexes and Cationic Pentanuclear ClustersEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 10 2005Maria Alexiou Abstract The use of di-2-pyridyl ketone oxime (Hpko)/X, "blends" (X, = PhCO2,, N3,, NCO,, acac,, NCS,) in zinc chemistry yields neutral tetranuclear and cationic pentanuclear clusters. Various synthetic procedures have led to the synthesis of compounds [Zn4(OH)2(O2CPh)2(pko)4]·3MeCN (1·3MeCN), [Zn4(OH)2(N3)2(pko)4]·4DMF (2·4DMF), [Zn4(OH)2(NCO)2(pko)4]·3DMF·H2O (3·3DMF·H2O), [Zn4(OH)2(acac)2(pko)4]·4CH2Cl2 (4·4CH2Cl2), [Zn5Cl2(pko)6][ZnCl(NCS)3]·2.5H2O·1.5MeOH (5·2.5H2O·1.5MeOH) and [Zn5(NCS)2(pko)6(MeOH)][Zn(NCS)4]·2.5H2O·MeOH (6·2.5H2O·MeOH). The structures of the six complexes have been determined by single-crystal X-ray crystallography. The tetranuclear molecules of 1,4 lie on a crystallographic inversion centre and have an inverse 12-metallacrown-4 topology. Two triply bridging hydroxides are accommodated in the centre of the metallacrown ring. The pko, ligands form a propeller configuration that imposes absolute stereoisomerism with , and , chirality. Two metal ions are in distorted O2N4 octahedral environments, whereas the rest are in severely distorted tetrahedral or trigonal bipyramidal environments. The five Zn ions of the cations of 5 and 6 are held together by six pko, ligands which adopt three different coordination modes; the chloro (5) and isothiocyanato (6) ligands are terminal. The five Zn ions define two nearly equilateral triangles sharing a common apex, and the novel Zn5 topology can be described as two "collapsed" 9-metallacrown-3 structures sharing a common Zn apex. Besides the pentanuclear cations, the structures of 5 and 6 contain slightly distorted tetrahedral [ZnCl(NCS)3]2, and [Zn(NCS)4]2, ions, respectively, with the isothiocyanato ligands binding the metal ion in a virtually linear fashion. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Abnormal alterations in the metabolic patterns of patients on valproate therapyJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 7 2002U. Kreher Four cases of abnormal metabolic patterns which were obtained from three infantile patients and one adult on valproate (valproic acid; 2-n-propyl-pentanoic acid) therapy are reported. Serum levels of valproate and 15 metabolites were measured by gas chromatography/mass spectrometry. A mentally retarded, 11-month-old boy developed an extremely altered metabolic profile after having been treated with valproate polytherapy for 3 months. The altered pattern included strongly elevated serum levels of the 4-ene as well as of the x-/x 1-metabolites, with the b-metabolites (2-ene; 2,3,-diene) being diminished. Two samples obtained previously had shown a common pattern. The infant died 3 weeks after the last sample had been taken. Two boys of the same age showed similar but less intense deviations in their metabolic profiles at the onset of valproate therapy. Within a few weeks they approached, in a step-wise fashion, the average pattern common for children under 3 years of age. The striking alterations were paralleled by the metabolic profiles of an adult patient who suffered from intrahepatic metastasis and renal insufficiency. From the close resemblance of the abnormal metabolic patterns it was concluded that liver dysfunction results in alteration of the whole metabolic system. Regular inspection of the entire profile of an individual might help to recognize conspicuous alterations in time to avoid severe side effects. [source] Monte Carlo study of cycloamylose: Chain conformation, radius of gyration, and diffusion coefficientBIOPOLYMERS, Issue 2 2002Yasushi Nakata Abstract Cyclic (1 , 4)-,- D -glucan chains with or without excluded volume have been collected from a huge number (about 107) of linear amylosic chains generated by the Monte Carlo method with a conformational energy map for maltose, and their mean-square radii of gyration ,S2, and translational diffusion coefficients D (based on the Kirkwood formula) have been computed as functions of x (the number of glucose residues in a range from 7 to 300) and the excluded-volume strength represented by the effective hard-core radius. Both ,S2,/x and D in the unperturbed state weakly oscillate for x < 30 and the helical nature of amylose appears more pronouncedly in cyclic chains than in linear chains. As x increases, these properties approach the values expected for Gaussian rings. Though excluded-volume effects on them are always larger in cycloamylose than in the corresponding linear amylose, the ratios of ,S2, and the hydrodynamic radius of the former to the respective properties of the latter in good solvents can be slightly lower than or comparable to the (asymptotic) Gaussian-chain values when x is not sufficiently large. An interpolation expression is constructed for the relation between the gyration-radius expansion factors for linear and cyclic chains from the present Monte Carlo data and the early proposed asymptotic relation with the aid of the first-order perturbation theories. © 2002 Wiley Periodicals, Inc. Biopolymers 64: 72,79, 2002 [source] HLA,DRB1 genotype associations in 793 white patients from a rheumatoid arthritis inception cohort: Frequency, severity, and treatment biasARTHRITIS & RHEUMATISM, Issue 9 2002James F. Fries Objective The HLA,DRB1 "shared epitope" (SE) genotypes are associated with rheumatoid arthritis (RA), but it remains controversial whether the association is with incidence, severity, or both, whether there are associations in seronegative patients, and whether different DRB1 alleles that contain the SE have similar effects on RA susceptibility and/or severity. The present study was undertaken to study these issues in a large cohort of patients with RA. Methods White patients with RA of <6 months' duration (n = 793) were enrolled in an inception cohort. HLA,DRB1 typing was performed, and patients were categorized into 21 DRB1 genotype groups. The disability index of the Health Assessment Questionnaire was the primary outcome measure. Results DRB1 associations in seronegative RA patients closely resembled those in controls. Of seropositive patients, 21% had 2 copies of the epitope, 52% had 1 copy, and 27% had none. However, not all genotypes with 1 copy were associated with increased susceptibility; for example, frequencies of DRB1*0404/X and *01/X did not differ from those in controls. Absolute differences between seropositive RA patients and controls were greatest for DRB1*0401 homozygosity (3.8% versus 0.8%, respectively) and *0401/0404 heterozygosity (4.7% versus 1.0%). DRB1*0404 was increased in frequency in seropositive RA but, unlike *0401, an increased frequency was seen only with 2 epitope copies. The relatively rare DRB1*10 had an unexpected association with seropositive RA, being present in 1.7% of seropositive RA patients and 0.7% of controls, and also showed a trend toward association with greater disease severity. The presence of 2 epitope copies was associated with increased frequency of seropositivity and younger age at disease onset, not with disease severity. Treatment indication bias was substantial and may have accounted for some of these effects. HLA,DRB1*0401/0404 was found much more frequently in men and in patients with a lower age at disease onset, and there was a trend toward a higher frequency of *0404/0401 in women. Conclusion This large inception cohort study confirms previously identified major associations and provides additional insights. Only one dominant association was found: *0401, which differs from other SE alleles in a single Lys-for-Arg substitution. The association of the rare DRB1*10 allele has not previously been postulated. Sex associations were confirmed. Associations with seronegative RA were not seen. Not all genotypes containing an SE copy showed increased susceptibility to RA. The association of SE genotypes found in this study related to disease susceptibility rather than severity. [source] LC,ESI-MS/MS analysis for the quantification of morphine, codeine, morphine-3-,- D -glucuronide, morphine-6-,- D -glucuronide, and codeine-6-,- D -glucuronide in human urineJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 11 2005Constance M. Murphy Abstract A liquid chromatographic-electrospray ionization-tandem mass spectrometric method for the quantification of the opiates morphine, codeine, and their metabolites morphine-3-,- D -glucuronide (M-3-G), morphine-6-,- D -glucuronide (M-6-G) and codeine-6-,- D -glucuronide (C-6-G) in human urine has been developed and validated. Identification and quantification were based on the following transitions: 286 to 201 and 229 for morphine, 300 to 215 and 243 for codeine, 644 to 468 for M-3-G, 462 to 286 for M-6-G, and 476 to 300 for C-6-G. Calibration by linear regression analysis utilized deuterated internal standards and a weighting factor of 1/X. The method was accurate and precise across a linear dynamic range of 25.0 to 4000.0 ng/ml. Pretreatment of urine specimens using solid phase extraction was sufficient to limit matrix suppression to less than 40% for all five analytes. The method proved to be suitable for the quantification of morphine, codeine, and their metabolites in urine specimens collected from opioid-dependent participants enrolled in a methadone maintenance program. Copyright © 2005 John Wiley & Sons, Ltd. [source] A validated method for the determination of nicotine, cotinine, trans -3,-hydroxycotinine, and norcotinine in human plasma using solid-phase extraction and liquid chromatography-atmospheric pressure chemical ionization-mass spectrometryJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 6 2006Insook Kim Abstract A liquid chromatographic-mass spectrometric method for the simultaneous determination of nicotine, cotinine, trans -3,-hydroxycotinine, and norcotinine in human plasma was developed and validated. Analytes and deuterated internal standards were extracted from human plasma using solid-phase extraction and analyzed by liquid chromatography/atmospheric pressure chemical ionization-mass spectrometric detection with selected ion monitoring (SIM). Limits of detection and quantification were 1.0 and 2.5 ng/ml, respectively, for all analytes. Linearity ranged from 2.5 to 500 ng/ml of human plasma using a weighting factor of 1/x; correlation coefficients for the calibration curves were > 0.99. Intra- and inter-assay precision and accuracy were < 15.0%. Recoveries were 108.2,110.8% nicotine, 95.8,108.7% cotinine, 90.5,99.5% trans -3,-hydroxycotinine, and 99.5,109.5% norcotinine. The method was also partially validated in bovine serum, owing to the difficulty of obtaining nicotine-free human plasma for the preparation of calibrators and quality control (QC) samples. This method proved to be robust and accurate for the quantification of nicotine, cotinine, trans -3,-hydroxycotinine, and norcotinine in human plasma collected in clinical studies of acute nicotine effects on brain activity and on the development of neonates of maternal smokers. Copyright © 2006 John Wiley & Sons, Ltd. [source] A simplified protein precipitation/mixed-mode cation-exchange solid-phase extraction, followed by high-speed liquid chromatography/mass spectrometry, for the determination of a basic drug in human plasmaRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 18 2006Y.-J. Xue A simplified protein precipitation/mixed-mode cation-exchange solid-phase extraction (PPT/SPE) procedure has been investigated. A mixture of acetonitrile and methanol along with formic acid was used to precipitate plasma proteins prior to selectively extracting the basic drug. After vortexing and centrifugation, the supernatants were directly loaded onto an unconditioned Oasis® MCX µElution 96-well extraction plate, where the protonated drug was retained on the negatively charged sorbent while interfering neutral lipids, steroids or other endogenous materials were washed away. Normal wash steps were deemed unnecessary and not used before sample elution. The sample extracts were analyzed under both conventional and high-speed liquid chromatography/tandem mass spectrometry (LC/MS/MS) conditions to examine the feasibility of the PPT/SPE procedure for human plasma sample clean-up. For the conventional LC/MS/MS method, chromatographic separation was achieved on a C18, 2.1,×,50,mm column with gradient elution (k,,=,5.5). The mobile phase contained 0.1% formic acid in water and 0.1% formic acid in acetonitrile. For the high-speed LC/MS/MS method, chromatographic separation was achieved on a C18, 2.1,×,10,mm guard column with gradient elution (k,,=,2.2, Rt,=,0.26,min). The mobile phase contained 0.1% formic acid in water and 0.001% trifluoroacetic acid in acetonitrile. Detection for both conventional and high-speed LC/MS/MS methods was by positive ion electrospray tandem mass spectrometry on a ThermoElectron Finnigan TSQ Quantum Ultra, where enhanced resolution (RP 2000; 0.2,amu) was used for high-speed LC/MS/MS. The standard curve, ranging from 0.5 to 100,ng/mL, was fitted to a 1/x weighted quadratic regression model. This combined PPT/SPE procedure effectively eliminated time-consuming sorbent conditioning and wash steps, which are essential for a conventional mixed-mode SPE procedure, but retained the advantages of both PPT (removal of plasma proteins) and mixed-mode SPE (analyte selectivity). The validation results demonstrated that this PPT/SPE procedure was well suited for both conventional and high-speed LC/MS/MS analyses. In comparison with a conventional mixed-mode SPE procedure, the simplified PPT/SPE process provided comparable sample extract purity. This simple sample clean-up procedure can be applied to other basic compounds with minor modifications of PPT solvents. Copyright © 2006 John Wiley & Sons, Ltd. [source] Two-dimensional hydrogen atom confined in circles, angles, and circular sectorsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 4 2005L. Chaos-Cador Abstract The Schrödinger equation for the 2D hydrogen atom is separable in circular coordinates (, = , , = tan,1y/x). In this article the energy eigenvalues and eigenfunctions of such an atom in three different situations of confinement inside (a) a circle (0 , , , ,0, 0 , , , 2,), (b) an angle (0 , , , ,, 0 , , , ,0), and (c) a circular sector (0 , , , ,0, 0 , , , ,0) are explicitly constructed. Characteristic properties of the atom in its ground state for each situation of confinement such as the polarizability for (a) and electric dipole moment for (b) and (c) are also evaluated. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 [source] Effects of Insulin-Like Growth Factor-1 Gene Transfer on Myosin Heavy Chains in Denervated Rat Laryngeal Muscle,THE LARYNGOSCOPE, Issue 2 2004Paul W. Flint MD Abstract Objectives/Hypothesis: To determine whether the myotrophic activity of human insulin-like growth factor (hIGF)-1 promotes restoration of normal myosin heavy chain (MHC) composition after nerve injury, MHC composition was analyzed after hIGF-1 gene transfer in denervated rat laryngeal muscle. Study Design: Animal model to study effects of gene transfer on laryngeal paralysis. Methods: In anesthetized rats, the left recurrent and superior laryngeal nerves are cut and suture ligated. A midline thyrotomy is performed, and the thyroarytenoid muscle is injected with a polyvinyl-based formulation containing a muscle specific expression system and hIGF-1 DNA (treatment group) or saline (control group). After 30 days, animals were killed, and the thyroarytenoid muscle was removed and processed for sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDSPAGE). Densitometric measurements were obtained to determine composition of MHCs. Results: As previously described, MHC composition in denervated laryngeal muscle was characterized by a decrease in type IIB and IIL and up-regulation of IIA/IIX. Compared with controls, hIGF-1 treated animals demonstrated a significant increase in expression of type IIB and IIL and a significant decrease in expression of type IIA/X. Conclusions: These findings suggest that the myotrophic effect of hIGF-1 gene transfer results in normalization of MHC composition in denervated muscle, with suppression of type IIA/X MHC and promotion of type IIL expression. [source] Microstructure and electrical properties of (1,x)(K0.5Na0.5)NbO3,x BiFeO3 piezoelectric ceramicsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 5 2008Xiang Li Abstract Lead,free ceramics (1,x)(K0.5Na0.5)NbO3,x BiFeO3 doped with 1 mol% Fe2O3 (KNNBF/x) have been synthesized by pressureless sintering. With the Fe2O3 doping, the KNNBF/x ceramics can be well sintered at 1085,1100 °C and exhibit a pure perovskite structure with x < 0.013. It was found that the crystal structure of the KNNBF/x ceramics changed from orthorhombic to tetragonal and then to pseudocubic phase with the increase of BiFeO3 content. The composition KNNBF/0.013 near the tetragonal symmetry that separates the orthorhombic and pseudocubic phases exhibits improved electrical properties: d33 = 173 pC/N, kp = 0.40, ,r = 905, tan , = 4%, Pr = 26 ,C/cm2, and Ec = 11.2 kV/cm, with a high Curie temperature (TC) of about 388 °C. Our results suggest that KNNBF/x are promising lead-free high temperature piezoelectric ceramics. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The MUC1 oncoprotein as a functional target: Immunotoxin binding to ,/, junction mediates cell killingINTERNATIONAL JOURNAL OF CANCER, Issue 1 2009Daniel B. Rubinstein Abstract MUC1, a heavily glycosylated mucin, has generated considerable interest as a target for tumor killing because of its overexpression in malignancies. Full-length MUC1 (MUC1/TM) is proteolytically cleaved after synthesis generating , and , subunits, which specifically bind in a noncovalent interaction. Although the , chain remains on the cell surface, the , chain binds in an on-and-off interaction. Most anti-MUC1 antibodies (Abs) described to date recognize epitopes within the highly immunogenic ,-chain tandem repeat. Because the ,-chain is shed, such Abs are sequestered and fail to reach MUC1-expressing cells. Immunizing with cDNA encoding MUC1/TM and the spliced MUC1/X isoform from which the tandem repeat has been deleted yielded antibodies to the MUC1 ,/, junction. Pseudomonas toxin PE38 linked to polyclonal anti-MUC1 ,/, junction Abs both bound and killed MUC1-positive malignant cells. Monoclonal DMC209 binds the MUC1 ,/, junction in both MUC1/X and MUC1/TM. When injected into SCID mice xenotransplanted with human breast cancer MDA-MB-231, monoclonal DMC209 showed significant in vivo tumor-suppressive activity. The MUC1/X ,/, junction presents a biologically-significant target in MUC1-expressing malignancies because (i) antibodies directed against cell-bound ,/, junction epitopes reach the intended cellular target, (ii) antibodies to junction epitope are internalized into cells, (iii) anti ,/, junction antibodies can effectively kill high MUC1-expressing cancer cells as antibody-toxin conjugates and (iv) antibodies targeting the MUC1 cell-bound ,/, junction results in tumor suppression in vivo. Our results indicate that cell-bound MUC1 ,/, junction, unlike shed alpha chain, represents a highly effective moiety for targeting and killing MUC1-expressing malignancies. © 2008 Wiley-Liss, Inc. [source] Alternative splicing generates a family of putative secreted and membrane-associated MUC4 mucinsFEBS JOURNAL, Issue 14 2000Nicolas Moniaux The MUC4 mucin gene encodes a putative membrane-anchored mucin with predicted size of 930 kDa, for its 26.5-kb allele. It is composed of two regions, the 850-kDa mucin-type subunit MUC4, and the 80-kDa membrane-associated subunit MUC4,. In this study, we cloned and characterized unique MUC4 cDNA sequences that differ from the originally published sequence. Eight alternative splice events located downstream of the central large tandem repeat array generated eight new, distinct cDNAs. The deduced sequences of these MUC4 cDNAs (sv1- MUC4 to sv8- MUC4, the full length cDNA being called sv0- MUC4) provided seven distinct variants, five secreted forms and two membrane-associated forms. Furthermore, two other alternative splicing events located on both sides of the tandem repeat array created two variants, MUC4/Y and MUC4/X, both lacking the central tandem repeat. Therefore, MUC4 can be expressed in three distinct forms, one membrane-bound, one secreted, and one lacking the hallmark feature of mucin, the tandem repeat array. Although no specific function has yet been discovered for the family of proteins putatively produced from the unique MUC4 gene, we suspect that the MUC4 proteins may be implicated in the integrity and renewal of the epithelium. [source] New enzymatic assay for serum urea nitrogen using urea amidolyaseJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 2 2003Shigeki Kimura Abstract We established an enzymatic assay for measurement of serum urea nitrogen using urea amidolyase (EC 3.5.1.45) from yeast species. The method is based on hydrolysis of urea by the enzyme. In this assay, we eliminated endogenous ammonium ion by use of glutamate dehydrogenase (EC 1.4.1.4). Then in the presence of urea amido-lyase, ATP, bicarbonate, magnesium, and potassium ions, ammonium ion was produced proportionally to urea concentration in serum. The concentra-tion of ammonium ion formed was determined by adding GLDH to produce NADP+ in the presence of 2-oxoglutarate and NADPH. We then monitored the change of absorbance at 340 nm. The inhibitory effect of calcium ion on this assay was eliminated by adding glyco-letherdiamine-N, N, N,, N,-tetraacetic acid to the reaction system. The with-in-assay coefficient of variations (CVs) of the present method were 1.80,3.76% (n = 10) at 2.8,19.0 mmol/L, respectively. The day-to-day CVs were 2.23,4.59%. Analytical recovery was 92,115%. The presence of ascorbic acid, bilirubin, hemoglobin, lipemic material, ammo-nium ion, or calcium ion did not affect this assay system. The correlation be-tween values obtained with the present method (y) and those by another enzy-matic method (x) was 0.997 (y = 1.02x , 0.10 mmol/L, Sy/x = 0.841, n = 100), with a mean difference of ,0.18 ± 0.86 mmol/L [(values by reference method , that of present method) ± SD] using the Bland-Altman technique. J. Clin. Lab. Anal. 17:52,56, 2003. © 2003 Wiley-Liss, Inc. [source] Homogenous enzyme immunoassay for cyclosporine in whole blood using the EMIT®2000 cyclosporine specific assay with the COBAS MIRA-plus analyzerJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 6 2001Shigeki Kimura Abstract We describe the evaluation of the EMIT®2000 cyclosporine specific assay kit, an enzyme-multiplied immunoassay for cyclosporine in whole blood, with a COBAS MIRA-plus analyzer. The enzyme used for the assay was glucose-6-phosphate dehydrogenase (EC 1.1.1.49 G6PDH) from Leuconostoc mesenteroides; the monoclonal antibody is fairly specific for cyclosporine, and is not reactive with most metabolites. The assay principle is based on competitive immunoassay with G6PDH-labeled cyclosporine and cyclosporine in sample to the anticyclosporine mouse monoclonal antibody binding site. The within-assay coefficient of variation (CV) of this method was 2.7,4.2% (n = 10) at the levels of 56.2,339.7 ,g/L. Day-to-day CVs ranged from 4.2,8.1% at the levels of 47.2,350.2 ,g/L. The within-day CVs ranged from 2.0,6.4% at the levels of 43.3,330.5 ,g/L. The functional detection limit was 24.9 ,g/L. Samples treated with pretreatment reagent were stable at least 5 hr. Calibration was stable at least 10 days. The analytical recovery was 81,109%. The correlation between values obtained with the EMIT®2000 cyclosporine specific assay kit (y) and fluorescence polarization immunoassay (FPIA) (TDxFLx) (x) was: y = 0.880x , 13.053 ,g/L (r = 0.984, Sy/x = 15.968, n = 71) with a mean difference of 31.42 ± 19.89 ,g/L ((TDxFLx , EMIT®2000) ± SD); for the FPIA (AxSYM) (x): y = 0.989 , 4.144 ,g/L (r = 0.981, Sy/x = 17.478, n = 71) with a mean difference of 5.56 ± 17.38 ,g/L ((AxSYM , EMIT®2000) ± SD); and for the radioimmunoassay (RIA, CYCLO-Trac SP) (x): y = 0.893 , 6.764 ,g/L (r = 0.993, Sy/x = 10.582, n = 71) with a mean difference of 22.18 ± 14.98 ,g/L ((RIA , EMIT®2000) ± SD) using the Bland-Altman technique. J. Clin. Lab. Anal. 15:319,323, 2001. © 2001 Wiley-Liss, Inc. [source] Epigenetic abnormality of SRY gene in the adult XY female with pericentric inversion of the Y chromosomeCONGENITAL ANOMALIES, Issue 2 2010Tomoko Mitsuhashi ABSTRACT In normal ontogenetic development, the expression of the sex-determining region of the Y chromosome (SRY) gene, involved in the first step of male sex differentiation, is spatiotemporally regulated in an elaborate fashion. SRY is expressed in germ cells and Sertoli cells in adult testes. However, only few reports have focused on the expressions of SRY and the other sex-determining genes in both the classical organ developing through these genes (gonad) and the peripheral tissue (skin) of adult XY females. In this study, we examined the gonadal tissue and fibroblasts of a 17-year-old woman suspected of having disorders of sexual differentiation by cytogenetic, histological, and molecular analyses. The patient was found to have the 46,X,inv(Y)(p11.2q11.2) karyotype and streak gonads with abnormally prolonged SRY expression. The sex-determining gene expressions in the patient-derived fibroblasts were significantly changed relative to those from a normal male. Further, the acetylated histone H3 levels in the SRY region were significantly high relative to those of the normal male. As SRY is epistatic in the sex-determination pathway, the prolonged SRY expression possibly induced a destabilizing effect on the expressions of the downstream sex-determining genes. Collectively, alterations in the sex-determining gene expressions persisted in association with disorders of sexual differentiation not only in the streak gonads but also in the skin of the patient. The findings suggest that correct regulation of SRY expression is crucial for normal male sex differentiation, even if SRY is translated normally. [source] An examination of different fetal specific antibodies and magnetic activated cell sorting for the enrichment of fetal erythroblasts from maternal bloodCONGENITAL ANOMALIES, Issue 3 2002Xiao Xi Zhao ABSTRACT, The aim of the present study was to compare the rates of fetal cells obtained after separation from maternal blood by magnetic activated cell sorting (MACS) using different fetal specific antibodies, and to evaluate the potential role of this method in the prenatal diagnosis of fetal trisomies. Peripheral blood samples were obtained from 42 women carrying chromosomally normal fetuses and from 4 women with aneuploid fetuses (2 cases of 47,XX,+18 and 2 of 47,XY,+21) at 9,20 weeks of gestation. After fetal cells were enriched by MACS with three different monoclonal antibodies (GPA, CD71, CD14), fluorescence in situ hybridization (FISH) with chromosome X, and Y-specific probes was performed to detect the rates of fetal cells in the samples sorted. FISH with chromosome 13-, 18-, and 21-specific probes was carried out to compare proportions of cells with three-signal nuclei in chromosomally normal and abnormal groups. In male infants, X-and Y-positive cells were detected in 80%, 73.3%, and 66.6% of samples after the separation by antibodies CD14, GPA, and CD71, respectively. The percentage of nuclei with three signals was increased in pregnancies with trisomy, ranging between 2% and 5.18%. Pregnancies with normal fetuses showed 0 to 3.7% of nuclei with three signals. The data demonstrate that fetal cell detection varies depending on the antibodies used for cell sorting. This study provides further evidence on the feasibility of screening for fetal chromosomal abnormalities by enriching maternal blood for fetal cells and using FISH. [source] Congenital Cardiovascular Disease in Turner SyndromeCONGENITAL HEART DISEASE, Issue 1 2008Carolyn A. Bondy MD ABSTRACT Turner syndrome (TS), or monosomy X, occurs in ,1/2000 live born females. Intelligence is normal and short stature is the most obvious and consistent feature of the syndrome. Congenital cardiovascular disease affects ,50% of individuals and is the major cause of premature mortality in adults. Unfortunately, this most important aspect of the syndrome has received little attention outside of pediatric medicine, and adult cardiological follow-up is seriously lacking. This review describes the spectrum of cardiovascular defects with particular attention to identifying risk factors for aortic dissection/rupture. X-chromosome genetic pathways implicated in Turner cardiovascular disease, including premature coronary artery disease, are discussed. Recent guidelines for diagnosis and treatment of girls and women with TS are reviewed. [source] The Dual Mode Microwave Afterglow Apparatus for Measuring the Electron Temperature Dependence of the Electron-Ion RecombinationCONTRIBUTIONS TO PLASMA PHYSICS, Issue 4 2008O. Miku Abstract Three dual mode microwave apparatus (one using S -band and two using X -band) have been developed to determine ambipolar diffusion and electron-ion recombination rates under conditions such that Tgas = 300K and Te is varied from 300 K to 6300 K, in the afterglow period of the dc glow discharge. TheTM010 cylindrical cavity (in S -band) and TM011 open cylindrical cavity (X -band) are used to determine the electron density during the afterglow period and a non-resonant waveguide mode is used to apply a constant microwave heating field to the electrons. To test the properties of the apparatus the neon afterglow plasma has been investigated. At Te = 300 K a value of , (Ne+2) = (1.7± 0.2) × 10,7cm3/s is obtained which is in good agreement with values of other investigators. Also similar variations of , as T,0.4e (S -band) and as T,0.42e (X -band) obeyed over the range 300 , Te , 6300K are in good agreement with some other previous measurements. The simplicity of the X-band microwave apparatus also allows the measurements of the gas temperature dependency and the study of electron attachment and may be used simultaneously with optical or mass spectrometry investigations. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Experimental Study and Modelling of Formation and Decay of Active Species in an Oxygen DischargeCONTRIBUTIONS TO PLASMA PHYSICS, Issue 1 2005A.-M. Diamy Abstract A microwave (2.45 GHz) oxygen discharge (3 hPa, 150 W, 50 mL.min,1) is studied by optical emission spectroscopy of O(5P) (line 777.4 nm) and of the atmospheric system of O2(head-line 759.4 nm). Calibration of the spectral response of the optical setup is used to determine the concentrations of O(5P) and O2(b). The concentration of the O(5P) atoms is in the range 108,109 cm,3 and the concentration of the O2(b) molecules is in the range 1014 , 2 × 1014 cm,3 along the discharge tube. An attempt is made to simulate the experimental results by using coupling the Boltzmann equation, homogeneous energy transfer V-V and V-T, heterogeneous reactions on the walls (energy transfer and recombination of atoms) and a kinetic scheme (electronic transfer and chemical reactions). The Boltzmann equation includes momentum transfer, inelastic and superelastic processes and e-e collisions. V-V and V-T transfer equations are obtained from the SSH theory and the kinetic scheme includes 65 reactions with 17 species [electrons e, ions O, and O2,, fundamental electronic neutral species O(3P), O2, O2(X,v), O3 and excited neutral species O2(a), O2(b), O2(A), O(1D), O(1S), O(5P), O(4d 5Do), O(5s 5So), O(3d 5Do) and O(4s 5So)]. A fair agreement between experimental results and modelling is obtained with the following set of fitting values: , heterogeneous deactivation coefficient for O2(b) , = 2.6 × 10,2; , rate constant of reaction [O(1D) + O(3P) , 2 O(3P)] k34 = 1.4 × 10,11 cm3.s,1; , electron concentration in the range 1010 , 1011 cm,3. Modelling shows that the recombination coefficient for oxygen atoms on the silica wall (range 1.4 × 10,3 , 0.2 × 10,3) is of the same order as the values obtained in a previous paper and that the ratio ([O] / 2 [O2]initial) is about 33,50%. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Phase transition behavior and structure of the thermotropic liquid crystal 6-{[(4,-{[(undecyl)carbonyl]oxy}biphenyl-4yl)carbonyl]oxy}-1-hexyneCRYSTAL RESEARCH AND TECHNOLOGY, Issue 9 2006Leijing Liu Abstract The phase transition behaviors and corresponding structures of 6-{[(4,-{[(undecyl)carbonyl]oxy}biphenyl-4yl)carbonyl]oxy}-1-hexyne (A4EE11) were investigated using differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and wide angle X-ray diffraction (WAXD). In comparison with the published homologues, 5-{[(4,-heptoxy-biphenyl-4-yl)carbonyl]oxy}-1-pentyne (A3EO7) which shows a monotropic smectic A (SmA) phase and a metastable monotropic smectic C (SmC) phase; 5-{[(4,-heptoxy-biphenyl-4-yl)oxy]carbonyl}- 1-pentyne (A3E'O7) that exhibits three enantiotropic stable liquid crystalline (LC) phases, SmA phase, SmC phase and smectic X (SmX) phase; 5-{[(4,-heptoxy-biphenyl-4-yl)carbonyl]oxy}-1-undecyne (A9EO7) which has a monotropic SmA phase and a metastable crystal phase, A4EE11 integrates the enantiotropy, monotropy and metastability of the LC phases of those three compounds. Upon cooling from isotropic state to room temperature, in the temperature range of 62.0 to 58.5°C, A4EE11 shows an enantiotropic smectic A (SmA) phase with a layer spacing d=32.69Å. Further lowering the temperature, it enters into a metastable monotropic smectic B (SmB) phase with a longer layer spacing d=34.22Å which has a tendency towards crystallization. The metastability of the liquid crystalline phase may associate to the linkage order of the ester bridge between the mesogenic core and the flexible spacer. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Diffusion couple studies of the Ti-Bi-Zn systemCRYSTAL RESEARCH AND TECHNOLOGY, Issue 9 2004G. P. Vassilev Abstract The system Ti-Bi-Zn has been investigated using diffusion couples consisting of solid Ti and liquid (Bi+Zn) phase. The diffusion paths at 400, 500, 700 and 800 °C have been traced by means of electron microprobe analyses. The growth constants of the diffusion layers are roughly assessed. The phase diagram data obtained in this investigation are compared with previous studies of equilibrated alloys. The existence of the ternary compound TiBiZn has been confirmed. The formation of another phase with approximate formulae Ti4Bi3Zn to Ti9Bi7Zn4 has been observed at high temperatures. The latter compound as well as the ternary extension of the TiXBiY (X , 5, Y , 6) phase react easily with air. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Preparation and investigation of (CuInSe2)x(2ZnSe)1-x and (CuInTe2)x(2ZnTe)1-x solid solution crystalsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 4 2004I. V. Bodnar Abstract The (CuInSe2)x(2ZnSe)1-x and (CuInTe2)x(2ZnTe)1-x solid solution crystals prepared by Bridgman method and chemical vapor transport have been studied. The nature of the crystalline phases, the local structure homogeneity and composition of these materials have been investigated by X-ray diffraction (XRD) and Electron Probe Microanalysis (EPMA) methods. The analysis revealed the presence of chalcopyrite-sphalerite phase transition between 0.6 , X , 0.7. Lattice constants, value of , position parameter and bond length between atoms were also calculated. It was found that the lattice parameters exhibit a linear dependence versus composition. The transmission spectra of solid solution crystals in the region of the main absorption edge were studied. It was established that the optical band gap of these materials changes non-linearly with the X composition. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] High temperature arsenic doping of CdHgTe epitaxial layersCRYSTAL RESEARCH AND TECHNOLOGY, Issue 1 2004A. Vlasov Abstract Experimental results on solid-state arsenic doping of the n-type bulk and ISOVPE epitaxial CdXHg1- XTe (X = 0.19 ÷ 0.3) alloys are presented. The arsenic doped thin epitaxial CdxHg1- xTe films (nAs , 5 · 1016 ÷ 1 · 1020 cm -3; d = 2 ÷ 5 ,m) obtained by RF sputtering in a mercury glow discharge were used as As diffusion sources. The arsenic diffusion and activation were carried out at temperatures T = 500 ÷ 600 °C under Hg vapour pressure. Immediately after the high temperature treatment all samples were annealed to annihilate point defects. The SIMS analysis was used for determination of the quantitative admixture distribution of As in the diffusion area. The arsenic electrical activity has been evaluated by means of differential Hall, resistivity and thermoemf measurements. The analysis of experimental data obtained as well as their comparison with previously obtained results has been performed. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Directional change produced by perpendicularly-oriented microgrooves is microtubule-dependent for fibroblasts and epitheliumCYTOSKELETON, Issue 5 2009Douglas W. Hamilton Abstract Anisotropic substrata such as micromachined grooves can control cell shape, orientation, and the direction of cell movement, a phenomena termed topographic guidance. Although many types of cells exhibit topographic guidance, little is known regarding cell responses to conflicting topographic cues. We employed a substratum with intersecting grooves in order to present fibroblasts and epithelial cells with conflicting topographic cues. Using time-lapse and confocal microscopy, we examined cell behavior at groove intersections. Migrating fibroblasts and epithelial cells typically extended a cell process into the intersection ahead of the cell body. After travelling along the "X" groove to enter the intersection, the leading lamellipodia of the cell body encountered the perpendicular "Y" groove, and spread latterly along the "Y" groove. The formation of lateral lamellipodia resulted in cells forming "T" or "L" morphologies, which were characterized by the formation of phosphotyrosine-rich focal adhesions at the leading edges. The "Y" groove did not prove an absolute barrier to cell migration, particularly for epithelial cells. Analysis of cytoskeletal distribution revealed that F-actin bundles did not adapt closely to the groove patterns, but typically did align to either the "X" or "Y" grooves. In contrast microtubules (MT) adapted closely to the walls. Inhibition of microtubule nucleation attenuated fibroblast and epithelial cell orientation within the intersection of the perpendicular grooves. We conclude that MT may be the prime determinant of fibroblast and epithelial cell conformation to conflicting topographies. Cell Motil. Cytoskeleton 2009. © 2009 Wiley-Liss, Inc. [source] Neural correlates of movement generation in the ,at-risk mental state'ACTA PSYCHIATRICA SCANDINAVICA, Issue 4 2010M. R. Broome Broome MR, Matthiasson P, Fusar-Poli P, Woolley JB, Johns LC, Tabraham P, Bramon E, Valmaggia L, Williams SCR, Brammer MJ, Chitnis X, McGuire PK. Neural correlates of movement generation in the ,at-risk mental state'. Objective:, People with ,prodromal' symptoms have a very high risk of developing psychosis. We examined the neurocognitive basis of this vulnerability by using functional MRI to study subjects with an at-risk mental state (ARMS) while they performed a random movement generation task. Method:, Cross-sectional comparison of individuals with an ARMS (n = 17), patients with first episode schizophreniform psychosis (n = 10) and healthy volunteers (n = 15). Subjects were studied using functional MRI while they performed a random movement generation paradigm. Results:, During random movement generation, the ARMS group showed less activation in the left inferior parietal cortex than controls, but greater activation than in the first episode group. Conclusion:, The ARMS is associated with abnormalities of regional brain function that are qualitatively similar to those in patients who have recently presented with psychosis but less severe. [source] The Efficacy of Curettage in Delineating Margins of Basal Cell Carcinoma Before Mohs Micrographic SurgeryDERMATOLOGIC SURGERY, Issue 9 2003Désirée Ratner MD Background. Curettage may be helpful as a preliminary step to outline the gross subclinical extensions of high-risk basal cell carcinomas (BCCs) before the first stage of Mohs micrographic surgery. Although many Mohs surgeons use curettage in the Mohs surgical setting, no prospective studies have as yet been performed that demonstrate the efficacy of curettage in delineating tumor margins before Mohs surgery. Objective. To document the efficacy of curettage in delineating BCC margins before Mohs micrographic surgery. Methods. This was a prospective evaluation of 599 patients with biopsy-proven BCCs treated with Mohs surgery. The preoperative dimensions of each tumor, the curetted dimensions before the first surgical stage, the proposed excisional margins before each surgical stage, and the final defect dimensions after each surgical stage were measured. The maximum curetted margin around each tumor was calculated and compared with typical Mohs excisional margins of 1, 2, 3, and 4 mm. A hypothetical 1-, 2-, 3-, or 4-mm excisional margin was added to the preoperative X and Y dimensions of each tumor, and the actual final defect sizes were compared with the hypothetical final defect sizes to determine whether an additional surgical stage would have been needed had curettage not been performed. The amount of tissue stretch occurring after specimen removal was calculated to determine whether tissue stretch falsely elevated the number of instances in which an additional surgical stage would have been needed had curettage not been performed. Results. The curetted margin around the observed extent of each tumor exceeded 1 mm in 87.6% of cases, 2 mm in 47.1% of cases, 3 mm in 19.7% of cases, and 4 mm in 5.7% of cases. The mean curetted margin was 1.7 mm. Taking a 1-mm margin in the first stage of Mohs surgery without first performing curettage would have necessitated an extra surgical stage in 99.2% of cases, whereas taking a 2-, 3-, or 4-mm margin would have necessitated an extra surgical stage in 93.0%, 88.1%, and 49.4% of cases, respectively. After calculating and eliminating the effects of tissue stretch, it was found that a 1-mm excisional margin taken in the first stage of Mohs surgery without first performing curettage would have necessitated an extra surgical stage in 99.0% of the cases. Taking a 2-, 3-, or 4-mm margin would have necessitated an extra surgical stage in 87.5%, 57.9%, and 29.5% of cases, respectively. Conclusion. Careful debulking and palpation with the curette significantly reduce the number of Mohs surgical stages required for BCC clearance. Even after taking the effects of tissue stretch into consideration, a significant proportion of tumors would still require an additional stage for tumor clearance without aggressive presurgical curettage. [source] The Effectiveness of Jobs Reservation: Caste, Religion and Economic Status in IndiaDEVELOPMENT AND CHANGE, Issue 3 2007Vani K. Borooah ABSTRACT This article investigates the effect of jobs reservation on improving the economic opportunities of persons belonging to India's Scheduled Castes (SC) and Scheduled Tribes (ST). Using employment data from the 55th NSS round, the authors estimate the probabilities of different social groups in India being in one of three categories of economic status: own account workers; regular salaried or wage workers; casual wage labourers. These probabilities are then used to decompose the difference between a group X and forward caste Hindus in the proportions of their members in regular salaried or wage employment. This decomposition allows us to distinguish between two forms of difference between group X and forward caste Hindus: ,attribute' differences and ,coefficient' differences. The authors measure the effects of positive discrimination in raising the proportions of ST/SC persons in regular salaried employment, and the discriminatory bias against Muslims who do not benefit from such policies. They conclude that the boost provided by jobs reservation policies was around 5 percentage points. They also conclude that an alternative and more effective way of raising the proportion of men from the SC/ST groups in regular salaried or wage employment would be to improve their employment-related attributes. [source] Requirement for ,B1-crystallin promoter of Xenopus laevis in embryonic lens development and lens regenerationDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 3 2005Nobuhiko Mizuno Regulation of the lens-specific ,B1-crystallin promoter in Xenopus laevis was investigated using transgenic larvae and tadpoles. Comparison of the promoter sequence with that of chicken ,B1-crystallin gene indicates significant sequence similarity over a span of several hundred base pairs starting from the transcriptional start site. Remarkably, PL-1 and PL-2 sequences identified in the chicken promoter as essential binding sites of MAF, Pax6 and Prox1 transcription factors were conserved. Mutations of X (Xenopus) PL-1 and XPL-2 sequences eliminated the promoter activity, indicating a conserved mechanism regulating ,B1-crystallin promoter among vertebrate species. A stepwise deletion of the promoter sequence starting from 2800 bp indicated that the proximal 260 bp directly upstream of the transcription initiation site is sufficient for eliciting lens-specific expression, but the 150 bp promoter sequence is inactive despite it containing the XPL-1 and XPL-2 sequences, suggesting the presence of an additional and essential regulatory sequence located between ,150 and ,260 bp. Activity of the ,B1-crystallin promoter during lens regeneration from cornea was examined using transgenic tadpoles and found to have the same dependence on promoter regions as in embryonic lens development, indicating that gene regulation is largely shared by the two lens-generating processes. [source] Fragile X-associated Tremor/Ataxia Syndrome (FXTAS)DEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 1 2004Paul J. Hagerman Abstract Carriers of fragile X mental retardation 1 (FMR1) premutation alleles (55 to 200 CGG repeats) are generally spared the more serious neurodevelopmental problems associated with the full-mutation carriers (>200 repeats) of fragile X syndrome. However, some adult male premutation carriers (55,200 repeats) develop a neurological syndrome involving intention tremor, ataxia, dementia, parkinsonism, and autonomic dysfunction. In excess of one-third of male premutation carriers over 50 years of age develop the fragile X- associated tremor/ataxia syndrome (FXTAS). FXTAS also represents a new form of inclusion disease, with eosinophilic intranuclear inclusions found throughout the brain in both neurons and astrocytes. Because FXTAS appears to be relatively specific to male premutation carriers, who are known to possess elevated levels of FMR1 mRNA, the neuropathology may arise as a consequence of a toxic gain-of-function of the mRNA itself, although this proposal requires additional direct testing. One of the critical needs at present is a better estimate for the prevalence of this disorder, because FXTAS is likely to be underdiagnosed in the adult movement disorders clinics. MRDD Research Reviews 2004;10:25,30. © 2004 Wiley-Liss, Inc. [source] Phenotypic variation and FMRP levels in fragile XDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 1 2004Danuta Z. Loesch Abstract Data on the relationships between cognitive and physical phenotypes, and a deficit of fragile X mental retardation 1 (FMR1) gene-specific protein product, FMRP, are presented and discussed in context with earlier findings. The previously unpublished results obtained, using standard procedures of regression and correlations, showed highly significant associations in males between FMRP levels and the Wechsler summary and subtest scores and in females between these levels and the full-scale intelligence quotient (FSIQ), verbal and performance IQ, and some Wechsler subtest scores. The published results based on data from 144 extended families with fragile X, recruited from Australia and the United States within a collaborative NIH-supported project, were obtained using robust modification of maximum likelihood in pedigrees. The results indicated that processing speed, short-term memory, and the ability to control attention, especially in the context of regulating goal-directed behavior, may be primarily affected by the FMRP depletion. The effect of this depletion on physical phenotype was also demonstrated, especially on body and head height and extensibility of finger joints. It is recommended that further studies should rely on more accurate measures of FMRP levels, and use of larger samples, to overcome extensive variability in the data. MRDD Research Reviews 2004;10:31,41. © 2004 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||