bluuebunny/crossref_metadata_2025_split huggingface dataset:
Do mood symptoms subdivide the schizophrenia phenotype? association of the GMP6A gene with a depression subgroup
Authors: Boks Marco P.M. , Hoogendoorn Mechteld , Jungerius Bart J. , Bakker Steven C. , Sommer Iris E. , Sinke Richard J. , Ophoff Roel A. , Kahn René S. 
Published: December 2007

AbstractGenetic studies of clinically defined subgroups of schizophrenia patients may reduce the phenotypic heterogeneity of schizophrenia and thus facilitate the identification of genes that confer risk to this disorder. Several latent class analyses have provided subgroups of psychotic disorders that show considerable consistency over these studies. The presence or absence of mood symptoms was found to contribute most to the delineations of these subgroups. In this study we used six previously published subtypes of psychosis derived from latent class analysis of a large sample of psychosis patients. In 280 schizophrenia patients and 525 healthy controls we investigated the associations of these subgroups with myelin related genes. After bonferroni correction we found an association of the glycoprotein M6A gene (GPM6A) with the subgroup of schizophrenia patients with high levels of depression (P‐corrected = 0.006). Borderline association of the microtubulin associated protein tau (MAPT) with a primarily non‐affective group of schizophrenia patients (P‐corrected = 0.052) was also observed. GPM6A modulates the influence of stress on the hippocampus in animals. Thus our findings could suggest that GMP6A plays a role in the stress‐induced hippocampal alterations that are found in psychiatric disorders in general and schizophrenia in particular. Overall, these finding suggests that investigating subgroups of schizophrenia based symptoms profile and particularly mood symptoms can facilitate genetic studies of schizophrenia. © 2007 Wiley‐Liss, Inc.
Association of complement factor H Y402H gene polymorphism with Alzheimer's disease
Authors: Zetterberg Madeleine , Landgren Sara , Andersson Malin E. , Palmér Mona Seibt , Gustafson Deborah R. , Skoog Ingmar , Minthon Lennart , Thelle Dag S. , Wallin Anders , Bogdanovic Nenad , Andreasen Niels , Blennow Kaj , Zetterberg Henrik 
Published: December 2007

AbstractAlzheimer's disease (AD) and age‐related macular degeneration (AMD) share several epidemiological and biochemical features. The present study aimed to assess the possible influence of the AMD‐associated complement factor H (CFH) Y402H (1277T > C) polymorphism on the risk of AD. Caucasian subjects (n = 800) meeting the criteria for probable (n = 717) or definite (n = 83) AD and Caucasian non‐demented controls (n = 1265) were included in this multi‐center case‐control study, in which genotype and allele frequencies of the CFH 1277T > C polymorphism were determined and related to diagnosis, APOE genotype, Mini‐Mental State Examination score (MMSE) and the cerebrospinal fluid (CSF) biomarkers total‐tau (T‐tau), phospho‐tau181 (P‐tau181), and β‐amyloid1–42 (Aβ1–42). The AMD‐associated CFH genotypes (1277CC and 1277TC) were overrepresented in subjects with AD as compared to control individuals (P = 0.029). Positive C carrier status was associated with an odds ratio (OR) for AD of 1.24 (95% confidence interval [CI] 1.02–1.50). When APOE ε4 carrier status was included in the regression model, this association was even stronger (OR 1.34, 95% CI: 1.08–1.65, P = 0.007). Subgroup analysis showed that the association between CFH C allele positivity and AD was only evident for individuals carrying the APOE ε4 allele. Positive C carrier status was also associated with lower levels of CSF Aβ1–42 selectively in the control group in an APOE ε4‐independent manner (P = 0.003). In conclusion, the CFH 1277T > C polymorphism seems to influence the risk of AD and there appears to be an interaction between CFH 1277C and APOE ε4 alleles. The CFH 1277C allele may predispose patients for co‐morbidity in AD and AMD. © 2007 Wiley‐Liss, Inc.
Identification of pharmacogenetic markers in smoking cessation therapy
Authors: Heitjan Daniel F. , Guo Mengye , Ray Riju , Wileyto E. Paul , Epstein Leonard H. , Lerman Caryn 
Published: December 2007

AbstractPharmacogenetic clinical trials seek to identify genetic modifiers of treatment effects. When a trial has collected data on many potential genetic markers, a first step in analysis is to screen for evidence of pharmacogenetic effects by testing for treatment‐by‐marker interactions in a statistical model for the outcome of interest. This approach is potentially problematic because (i) individual significance tests can be overly sensitive, particularly when sample sizes are large; and (ii) standard significance tests fail to distinguish between markers that are likely, on biological grounds, to have an effect, and those that are not. One way to address these concerns is to perform Bayesian hypothesis tests [Berger (1985) Statistical decision theory and Bayesian analysis. New York: Springer; Kass and Raftery (1995) J Am Stat Assoc 90:773–795], which are typically more conservative than standard uncorrected frequentist tests, less conservative than multiplicity‐corrected tests, and make explicit use of relevant biological information through specification of the prior distribution. In this article we use a Bayesian testing approach to screen a panel of genetic markers recorded in a randomized clinical trial of bupropion versus placebo for smoking cessation. From a panel of 59 single‐nucleotide polymorphisms (SNPs) located on 11 candidate genes, we identify four SNPs (one each onCHRNA5andCHRNA2and two onCHAT) that appear to have pharmacogenetic relevance. Of these, the SNP onCHRNA5is most robust to specification of the prior. An unadjusted frequentist test identifies seven SNPs, including these four, none of which remains significant upon correction for multiplicity. In a panel of 43 randomly selected control SNPs, none is significant by either the Bayesian or the corrected frequentist test. © 2007 Wiley‐Liss, Inc.
Association analysis of 528 intra‐genic SNPs in a region of chromosome 10 linked to late onset Alzheimer's disease
Authors: Morgan A.R. , Hamilton G. , Turic D. , Jehu L. , Harold D. , Abraham R. , Hollingworth P. , Moskvina V. , Brayne C. , Rubinsztein D.C. , Lynch A. , Lawlor B. , Gill M. , O'Donovan M. , Powell J. , Lovestone S. , Williams J. , Owen M.J. 
Published: December 2007

AbstractLate‐onset Alzheimer's disease (LOAD) is a genetically complex neurodegenerative disorder. Currently, only the ε4 allele of the Apolipoprotein E gene has been identified unequivocally as a genetic susceptibility factor for LOAD. Others remain to be found. In 2002 we observed genome‐wide significant evidence of linkage to a region on chromosome 10q11.23–q21.3 [Myers et al. (2002) Am J Med Genet 114:235–244]. Our objective in this study was to test every gene within the maximum LOD‐1 linkage region, for association with LOAD. We obtained results for 528 SNPs from 67 genes, with an average density of 1 SNP every 10 kb within the genes. We demonstrated nominally significant association with LOAD for 4 SNPs: rs1881747 near DKK1 (P = 0.011, OR = 1.24), rs2279420 in ANK3 (P = 0.022, OR = 0.79), rs2306402 in CTNNA3 (P = 0.024, OR = 1.18), and rs5030882 in CXXC6 (P = 0.046, OR = 1.29) in 1,160 cases and 1,389 controls. These results would not survive correction for multiple testing but warrant attempts at confirmation in independent samples. © 2007 Wiley‐Liss, Inc.
Identification of FMRP‐associated mRNAs using yeast three‐hybrid system
Authors: Zou Ke , Liu Jian , Zhu Ning , Lin Jianhong , Liang Qi , Brown W. Ted , Shen Yan , Zhong Nanbert 
Published: December 2007

AbstractFragile X syndrome, one of the most common forms of inherited mental retardation, results from the absence of the fragile X mental retardation protein (FMRP), which is encoded by the fragile X mental retardation gene 1 (FMR1). FMRP is an RNA‐binding protein involved in translational regulation of targeted mRNAs. Identification of targeted mRNAs associated with FMRP is important to understand the function of FMRP and the pathogenic basis of the fragile X syndrome. Employing a yeast three‐hybrid system and a human fetal hippocampus cDNA library, we identified 22 candidate target mRNAs, and 18 of them were confirmed to be associated with FMRP in vitro by gel retardation. Some of these mRNAs code for structural proteins, enzymes or proteins involved in cellular processes, especially in the development and function of neural system. To further investigate the role of FMRP in regulating targeted gene expression, we analyzed the expression profile of TXNRD1, one of the candidate mRNAs, after knocking down the expression of endogenous FMRP by siRNA. The results showed that endogenous TXNRD1 translation increased along with depletion of FMRP, which suggested FMRP negatively regulates TXNRD1 translation. © 2007 Wiley‐Liss, Inc.
Regulation of a novel αN‐catenin splice variant in schizophrenic smokers
Authors: Mexal Sharon , Berger Ralph , Pearce Lucy , Barton Amanda , Logel Judy , Adams Catherine E. , Ross Randal G. , Freedman Robert , Leonard Sherry 
Published: December 2007

AbstractThe αN‐catenin (CTNNA2) gene represents a promising candidate gene for schizophrenia based upon previous genetic linkage, expression, and mouse knockout studies. CTNNA2 is differentially regulated by smoking in schizophrenic patients. In this report, the genomic structure of a primate‐specific αN‐catenin splice variant (αN‐catenin III) is described. A comparison of αN‐catenin III mRNA expression across postmortem hippocampi from schizophrenic and non‐mentally ill smokers and non‐smokers revealed a significant decrease in expression among patient non‐smokers compared to all other groups. The recent evolutionary divergence of this gene, as well as the differences in gene expression in postmortem brain of schizophrenic non‐smokers, supports the role of αN‐catenin III as a novel disease susceptibility gene. © 2007 Wiley‐Liss, Inc.
Association of DAO and G72(DAOA)/G30 genes with bipolar affective disorder
Authors: Prata Diana , Breen Gerome , Osborne Sarah , Munro Janet , St. Clair David , Collier David 
Published: December 2007

AbstractThere is growing evidence of partial aetiological overlap between schizophrenia and bipolar disorder (BP) from linkage analysis, genetic epidemiology and molecular genetics studies. In the present study we investigated whether individual polymorphisms or haplotypes of the DAO and G72(DAOA)/G30 genes, which have been previously implicated in schizophrenia, are also associated with bipolar disorder. For each gene, we genotyped 213 cases and 197 controls for SNPs previously associated with schizophrenia: rs2111902 (MDAAO‐4), rs3918346 (MDAAO‐5), rs3741775 (MDAAO‐6) and rs3918347 (MDAAO‐7) in DAO and rs746187 (M7), rs3916966 (M13), rs2391191 (M15) and rs3916972 (M25) in G72. Although none of the individual SNPs in these genes reached statistical significance, we found haplotype wise associations with bipolar disorder for both genes. These included a two‐SNP haplotype in DAO (rs2111902‐A and rs3918346‐T; global P = 0.003, individual P = 0.002, Z = 3.1) and a two‐SNP haplotype for G72(DAOA)/G30 (rs746187‐G and rs3916972‐G; global P = 0.05; individual P = 0.005, Z = 2.81). However, we found no evidence for an epistatic interaction between the SNPs and/or haplotypes of the two genes. In summary, our findings provide some support for the individual involvement of DAO and G72(DAOA)/G30 in the etiology of bipolar disorder. © 2007 Wiley‐Liss, Inc.
Different‐sized duplications of Xq28, including MECP2, in three males with mental retardation, absent or delayed speech, and recurrent infections
Authors: Smyk M. , Obersztyn E. , Nowakowska B. , Nawara M. , Cheung S.W. , Mazurczak T. , Stankiewicz P. , Bocian E. 
Published: December 2007

AbstractIn XY males, duplication of any part of the X chromosome except the pseudoautosomal region leads to functional disomy of the corresponding genes. We describe three unrelated male patients with mental retardation (MR), absent or delayed speech, and recurrent infections. Using high‐resolution comparative genomic hybridization (HR‐CGH), whole genome array comparative genomic hybridization (array CGH), fluorescent in situ hybridization (FISH), and multiplex ligation probe amplification (MLPA), we have identified and characterized two different unbalanced Xq27.3‐qter translocations on the Y chromosome (approx. 9 and 12 Mb in size) and one submicroscopic interstitial duplication (approx. 0.3–1.3 Mb) involving the MECP2 gene. Despite the differences in size of the duplicated segments, the patients share a clinical phenotype that overlaps with the features described in patients with MECP2 duplication. Our data confirm previous observations that MECP2 is the most important dosage‐sensitive gene responsible for neurologic development in patients with duplications on the distal part of chromosome Xq. © 2007 Wiley‐Liss, Inc.
Impact of the Fragile X mental retardation 1 (FMR1) gene premutation on neuropsychiatric functioning in adult males without fragile X‐associated Tremor/Ataxia syndrome: A controlled study
Authors: Kogan Cary S. , Turk Jeremy , Hagerman Randi J. , Cornish Kim M. 
Published: December 2007

AbstractFragile X Syndrome is the most common heritable form of mental retardation caused by silencing of the FMR1 gene, which arises from intergenerational trinucleotide repeat expansion leading to full mutation. An intermediary carrier condition, known as the premutation, is characterized by expansion up to 200 repeats without concomitant gene silencing. This prevalent allelic variant was initially thought to be free of phenotypic effects. However, recent reports have identified a degenerative disease, Fragile X‐associated Tremor/Ataxia Syndrome (FXTAS) in older men as well as premature ovarian failure in women. Previously reports are inconsistent regarding the neuropsychiatric phenotype associated with premutation due to small sample sizes, ascertainment bias, lack of adequate control groups, administration of measures with poor psychometric properties, and the confounding effects of FXTAS. We addressed these problems by conducting a controlled study of male carriers (n = 40) of the premutation without manifest symptoms of FXTAS, comparing their responses on specific, reliable, and valid measures of neuropsychiatric functioning to those of individuals with shared family environment (n = 22) and non‐carrier comparison males (n = 43). Multivariate analyses revealed that the premutation confers significant risk for working memory difficulties, an associated feature of Attention‐Deficit Disorder. Furthermore, both the family controls and men with premutation exhibited higher rates of Alcohol Abuse as compared to non‐carrier control men. These findings highlight the importance of recognizing the distinct phenotypic outcomes that characterize the Fragile X premutation and the subtle risk factors that can act as precursors to more significant psychiatric impairment. © 2007 Wiley‐Liss, Inc.
Preparation of PFSA‐PVA/PSf hollow fiber membrane for IPA/H2O pervaporation process
Authors: Lang Wan‐Zhong , Tong Wei , Xu Zhen‐Liang 
Published: December 2007

AbstractUsing Na+form of perfluorosulfonic acid (PFSA) and poly(vinyl alcohol) (PVA) as coating materials, polysulfone (PSf) hollow fiber ultrafiltration membrane as a substrate membrane, PFSA‐PVA/PSf hollow fiber composite membrane was fabricated by dip‐coating method. The membranes were post‐treated by two methods of heat treatment and by both heat treatment and chemical crosslinking. Maleic anhydride (MAC) aqueous solution was used as chemical crosslinking agent using 0.5 wt % H2SO4as a catalyst. PFSA‐PVA/PSf hollow fiber composite membranes were used for the pervaporation (PV) separation of isopropanol (IPA)/H2O mixture. Based on the experimental results, PFSA‐PVA/PSf hollow fiber composite membrane is suitable for the PV dehydration of IPA/H2O solution. With the increment of heat treatment temperature, the separation factor increased and the total permeation flux decreased. The addition of PVA in PFSA‐PVA coating solution was favorable for the improvement of the separation factor of the composite membranes post‐treated by heat treatment. Compared with the membranes by heat treatment, the separation factors of the composite membranes post‐treated by both heat treatment and chemical crosslinking were evidently improved and reached to be about 520 for 95/5 IPA/water. The membranes post‐treated by heat had some cracks which disappeared after chemical crosslinking for a proper time. Effects of feed temperature on PV performance had some differences for the membranes with different composition of coating layer. The composite membranes with the higher mass fraction of PVA in PFSA‐PVA coating solution were more sensitive to temperature. It was concluded that the proper preparation conditions for the composite membranes were as follows: firstly, heated at 160°C for 1 h, then chemical crosslinking at 40°C for 3 h in 4% MAC aqueous solution. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Influence of fillers on the properties of a phenolic resin cured in acidic medium
Authors: Laza J. M. , Alonso J. , Vilas J. L. , Rodríguez M. , León L. M. , Gondra K. , Ballestero J. 
Published: December 2007

AbstractThe curing behavior of a phenolic resol resin in the presence of p‐toluensulphonic acid is reported herein. The gel time of different systems has been determined by thermal scanning rheometry. Thermal and mechanical properties of the resin have been modified by the addition of varying amounts of fillers, talc, and kaolin. dynamic mechanical thermal analysis is used to determine the mechanical properties of the systems and the influence of the fillers and the postcuring. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
The influence of in situ modification of silica on filler network and dynamic mechanical properties of silica‐filled solution styrene–butadiene rubber
Authors: Wu You‐Ping , Zhao Qing‐Song , Zhao Su‐He , Zhang Li‐Qun 
Published: December 2007

AbstractThe influence of in situ modification of silica with bis‐(3‐(triethoxysilyl)‐propyl)‐tetrasulfide (TESPT) on filler network in silica filled solution SBR compound was investigated. In situ modification greatly increased the bound rubber content. TEM observation of silica gel showed that bridging and interlocking of absorbed chains on the surface of silica particles formed the filler network. Rubber processing analyzer (RPA) was used to characterize the filler network and interaction between silica and rubber by strain and temperature sweeps. In situ modification improved the dispersion of silica, and in the meantime, the chemical bonds were formed between silica and rubber, which conferred the stability of silica dispersion during the processing. Compared to the compound without in situ modification, the compound with in situ modification of silica exhibited higher tan δ at low strains and lower tan δ at high strains, which can be explained in terms of filler network in the compounds. After in situ modification, DMTA results showed silica‐filled SSBR vulcanizate exhibited higher tan δ in the temperature range of −30 to 10°C, and RPA results showed that it had lower tan δ at 60°C when the strain was more than 3%. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Thermal gradient solid state forming of polypropylene
Authors: Lo J. C. W. , Shinozaki D. M. 
Published: December 2007

AbstractThe near surface region of polypropylene was hardened in a forming process, which involved a large shear strain in a strong thermal gradient. The optimal processing conditions were estimated by modeling the temperature distribution in the deformation zone. Microindentation testing was used to characterize the corresponding depth‐dependent mechanical properties. The mechanical gradient, which developed after forming, was consistent with the observed variation in microstrucfture. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Toughening of an epoxy resin with an isocyanate‐terminated polyether
Authors: Soares Bluma G. , Gonçalez Viviane , Galimberti Rurik , Sirqueira Alex S. , Barcia Fabio L. , Simão Renata A. 
Published: December 2007

AbstractA low‐molar‐mass, hydroxyl‐terminated polyether [polypropylene glycol/poly(ethylene glycol) copolymer (POPE)] was functionalized with isocyanate groups and used to improve the impact resistance of a diglycidyl ether of bisphenol A based epoxy resin cured with triethylene tetramine (TETA). The effect of polyether‐based modifiers (with and without NCO groups) on the curing rate of the epoxy/TETA system was investigated with rheological techniques. The NCO‐functionalized polyether reduced the gel time, and this indicated an accelerating effect of the curing process. In addition, a significant improvement in the impact resistance was observed with only a slightly detrimental effect on the stiffness and mechanical strength. Scanning electron microscopy of the corresponding epoxy network revealed a homogeneous morphology with no phase separation. The miscibility of NCO‐modified POPE and the epoxy resin was also confirmed with atomic force microscopy. The glass‐transition temperature of the epoxy networks was also investigated with dynamic mechanical techniques. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis and characterization of polyethylene modified through phase‐transfer‐catalyzed graft copolymerization
Authors: Kaur Inderjeet , Dogra Ramesh , Kaur Simrat , Deepika N. 
Published: December 2007

AbstractIn an effort to impart biodegradability, polyethylene (PE) was modified through the graft copolymerization of vinyl monomers such as acrylamide (AAm) and acrylic acid (AAc) by a phase‐transfer‐catalyst method. The grafting percentage of AAm and AAc for PE was found to be dependent on the dibenzoyl peroxide concentration, monomer concentration, time, temperature, and concentration of the phase‐transfer catalyst. Some AAm‐ and AAc‐grafted PE samples were prepared by chemical, UV, and γ‐radiation methods. The biodegradation of samples of PE, polyethylene‐g‐polyacrylamide, and polyethylene‐g‐poly(acrylic acid) prepared by all these methods was studied. The weight loss of the samples over a period of time was observed with soil‐burial tests. The grafted samples prepared by the phase‐transfer‐catalyst method showed better biodegradation results than those prepared by other methods of grafting. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
The study of melt grafting mechanism of acrylic acid and butyl acrylate onto low density polyethylene and its application as internal plasticizer
Authors: Ding Shenglong , Liu Mingzhu , Fang Haibin 
Published: December 2007

AbstractMelt grafting of acrylic acid (AA) and butyl acrylate (BA) (equal molar ratios) onto low‐density polyethylene (LDPE) was carried out in Haake internal mixter by free radical grafting copolymerization. The graft degree of AA and BA in the grafted LDPE (LDPE‐g‐(AA+BA)) was determined by FTIR. The influences of initiator on the graft degree of AA and BA, melt flow rate (MFR), and gel content were investigated, and the optimum conditions were obtained. The successive self‐nucleation/annealing (SSA) thermal fraction method was used to characterize the molecular structure and polydispersity of LDPE‐g‐(AA+BA) with various graft degrees. The effects of thermal fraction parameters on fraction of LDPE‐g‐(AA+BA) were investigated. On the basis of the results of SSA, the grafting reaction mechanism of AA and BA onto LDPE was proposed, i.e., grafting reaction preferentially occurred on the tertiary carbons of LDPE. The grafted LDPE possessed suitable reactivity and rheological property. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008