bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chronic persistent cough in the community: a questionnaire survey
Authors: Everett Caroline F , Kastelik Jack A , Thompson Rachel H , Morice Alyn H 
Published: May 2007

Abstract

Background
Chronic cough is a common symptom which causes significant levels of morbidity. It is becoming increasingly well characterised by research taking place in specialist cough clinics, where successful treatment rates are high. However, there is a paucity of data regarding the symptom complex of chronic cough in the community. This report details the results of a postal questionnaire survey sent to individuals requesting further information on chronic cough.

Methods
856 chronic cough questionnaires were sent out to members of the public who requested an information sheet following a national UK radio broadcast. Information regarding demography, history of cough, previous treatment and physical, psychological and social effects of the cough was elicited.

Results
373 completed questionnaires were returned. Mean age was 65.3 years (SD 12.0, range 9–88 years). 73% were female and 2% current smokers. Median duration of cough was 6.5 years. 66% had no other coexisting respiratory diagnosis, whilst 24% reported asthma. Of those who responded, 91% had consulted a general practitioner regarding the cough and of them, 85% had been prescribed some sort of treatment. 61% had seen at least one hospital specialist. Commonly reported associated physical symptoms included breathlessness (55%), wheeze (37%), fatigue (72%) and disturbed sleep (70%). Incontinence occurred in 55% of women. Similarly, the majority reported psychological effects such as anger or frustration (83%), anxiety (69%) and depression (55%). 64% felt that the cough interfered with their social life.

Conclusion
Chronic cough causes a high level of morbidity in the community, which results in a correspondingly high rate of healthcare utilisation. Demography and symptomatology seems to be similar to that reported from specialist centres, but successful treatment of the cough was uncommon, despite a high number of medical consultations in both primary and secondary care. If understanding of this debilitating but eminently treatable condition is enhanced, management of chronic cough will improve and many patients will be helped.
Decline of nucleotide excision repair capacity in aging Caenorhabditis elegans
Authors: Meyer Joel N , Boyd Windy A , Azzam Gregory A , Haugen Astrid C , Freedman Jonathan H , Van Houten Bennett 
Published: May 2007

Abstract
Background
Caenorhabditis elegans is an important model for the study of DNA damage and repair related processes such as aging, neurodegeneration, and carcinogenesis. However, DNA repair is poorly characterized in this organism. We adapted a quantitative polymerase chain reaction assay to characterize repair of DNA damage induced by ultraviolet type C (UVC) radiation in C. elegans, and then tested whether DNA repair rates were affected by age in adults.

Results
UVC radiation induced lesions in young adult C. elegans, with a slope of 0.4 to 0.5 lesions per 10 kilobases of DNA per 100 J/m2, in both nuclear and mitochondrial targets. L1 and dauer larvae were more than fivefold more sensitive to lesion formation than were young adults. Nuclear repair kinetics in a well expressed nuclear gene were biphasic in nongravid adult nematodes: a faster, first order (half-life about 16 hours) phase lasting approximately 24 hours and resulting in removal of about 60% of the photoproducts was followed by a much slower phase. Repair in ten nuclear DNA regions was 15% and 50% higher in more actively transcribed regions in young and aging adults, respectively. Finally, repair was reduced by 30% to 50% in each of the ten nuclear regions in aging adults. However, this decrease in repair could not be explained by a reduction in expression of nucleotide excision repair genes, and we present a plausible mechanism, based on gene expression data, to account for this decrease.

Conclusion
Repair of UVC-induced DNA damage in C. elegans is similar kinetically and genetically to repair in humans. Furthermore, this important repair process slows significantly in aging C. elegans, the first whole organism in which this question has been addressed.
Preparation of Cyclohexene-d10 by H/D-Exchange Reaction
Authors: Ishibashi Kenichi , Matsubara Seijiro 
Published: May 2007

Abstract
Preparation of fully deuterium-labeled cyclohexene by H/D-exchange reaction was performed efficiently in the presence of ruthenium catalyst under irradiation of microwaves. The reaction proceeds via a repetition of hydroruthenation and β-elimination.
Resolving the Genetic and Environmental Sources of the Correlation Between Height and Intelligence: A Study of Nearly 2600 Norwegian Male Twin Pairs
Authors: Sundet Jon Martin , Tambs Kristian , Harris Jennifer R. , Magnus Per , Torjussen Tore M. 
Published: May 2007

AbstractThe main aim of this paper was to resolve the correlation between intelligence test scores and standing height into genetic and environmental components. Data on 1181 identical and 1412 fraternal twin pairs (all males) were retrieved by matching files from the Norwegian Army with twin registries. The data were analyzed by means of a structural equation model comprising latent genetic, shared environmental and nonshared environmental factors and correlations between them. A major part of the height–intelligence correlation was due to correlated shared environments (59% of the phenotypic height–intelligence correlation), but statistically significant effects of correlated genes and nonshared environments were also found (respectively 35% and 6% of the phenotypic correlation).
Genetic and Environmental Influences on Temperament in the First Year of Life: The Puerto Rico Infant Twin Study (PRINTS)
Authors: Silberg Judy L. , San Miguel Vivian Febo , Murrelle E. Lenn , Prom Elizabeth , Bates John E. , Canino Glorisa , Egger Helen , Eaves Lindon J. 
Published: May 2007

AbstractThree dimensions of temperament — difficult temperament, unadaptablility and unsociability — were assessed in the first year of life by maternal interview in twins born in Puerto Rico during 2001 and 2002. Eight hundred and sixty-five eligible mothers (80%) were traced and interviewed. Model- fitting results showed that additive genetic factors and the individual specific environment contributed to variation in all three dimensions. In addition, the pattern of variances and correlations suggested that sibling contrast effects influence ratings of difficult temperament. Moderate effects of the shared environment contributed to ratings of adaptability and sociability. There was a significant genetic correlation between difficult temperament and unadaptability. Genetic and environmental effects do not differ significantly between boys and girls. The study is the first population-based study of Puerto Rican twins and one of few to attempt the assessment of behavior in the first year. Preliminary results for difficult temperament and sociability were consistent with those in other populations and ages. In contrast, a significant effect of the shared environment on the temperamental trait of unadaptability has not been reported previously.
A Comparison of DNA Pools Constructed Following Whole Genome Amplification for Two-Stage SNP Genotyping Designs
Authors: Zhao Zhen Zhen , Nyholt Dale R. , James Michael R. , Mayne Renee , Treloar Susan A. , Montgomery Grant W. 
Published: May 2007

AbstractGenotyping in DNA pools reduces the cost and the time required to complete large genotyping projects. The aim of the present study was to evaluate pooling as part of a strategy for fine mapping in regions of significant linkage. Thirty-nine single nucleotide polymorphisms (SNPs) were analyzed in two genomic DNA pools of 384 individuals each and results compared with data after typing all individuals used in the pools. There were no significant differences using data from either 2 or 8 heterozygous individuals to correct frequency estimates for unequal allelic amplification. After correction, the mean difference between estimates from the genomic pool and individual allele frequencies was .033. A major limitation of the use of DNA pools is the time and effort required to carefully adjust the concentration of each individual DNA sample before mixing aliquots. Pools were also constructed by combining DNA after Multiple Displacement Amplification (MDA). The MDA pools gave similar results to pools constructed after careful DNA quantitation (mean difference from individual genotyping .040) and MDA provides a rapid method to generate pools suitable for some applications. Pools provide a rapid and cost-effective screen to eliminate SNPs that are not polymorphic in a test population and can detect minor allele frequencies as low as 1% in the pooled samples. With current levels of accuracy, pooling is best suited to an initial screen in the SNP validation process that can provide high-throughput comparisons between cases and controls to priori- tize SNPs for subsequent individual genotyping.
Evaluating Whole Genome Amplification via Multiply-Primed Rolling Circle Amplification for SNP Genotyping of Samples With Low DNA Yield
Authors: Silander Kaisa , Komulainen Kati , Ellonen Pekka , Jussila Minttu , Alanne Mervi , Levander Minna , Tainola Päivi , Kuulasmaa Kari , Salomaa Veikko , Perola Markus , Peltonen Leena , Saarela Janna 
Published: May 2007

AbstractThe amount of available DNA is often a limiting factor in pursuing genetic analyses of large-scale population cohorts. An association between higher DNA yield from blood and several phenotypes associated with inflammatory states has recently been demonstrated, suggesting that exclusion of samples with very low DNA yield may lead to biased results in statistical analyses. Whole genome amplification (WGA) could present a solution to the DNA concentration-dependent sample selection. The aim was to thoroughly assess WGA for samples with low DNA yield, using the multiply-primed rolling circle amplification method. Fifty-nine samples were selected with the lowest DNA yield (less than 7.5µg) among 799 samples obtained for one population cohort. The genotypes obtained from two replicate WGA samples and the original genomic DNA were compared by typing 24 single nucleotide polymorphisms (SNPs). Multiple genotype discrepancies were identified for 13 of the 59 samples. The largest portion of discrepancies was due to allele dropout in heterozygous genotypes in WGA samples. Pooling the WGA DNA replicates prior to genotyping markedly improved genotyping reproducibility for the samples, with only 7 discrepancies identified in 4 samples. The nature of discrepancies was mostly homozygote genotypes in the genomic DNA and heterozygote genotypes in the WGA sample, suggesting possible allele dropout in the genomic DNA sample due to very low amounts of DNA template. Thus, WGA is applicable for low DNA yield samples, especially if using pooled WGA samples. A higher rate of genotyping errors requires that increased attention be paid to genotyping quality control, and caution when interpreting results.
Estimation of Prevalence of DSM-IV and Latent Class-Defined ADHD Subtypes in a Population-Based Sample of Child and Adolescent Twins
Authors: Neuman Rosalind J. , Sitdhiraksa Nantawat , Reich Wendy , Ji Ted H.-C. , Joyner Cynthia A. , Sun Ling-Wei , Todd Richard D. 
Published: May 2007

AbstractThe goal of this study is to determine the prevalence and age of onset of Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSMIV; American Psychiatric Association, 1994) and latent class-derived attention deficit/hyperactivity disorder (ADHD) subtypes in a population-based twin sample of boys and girls. Missouri birth records identified families with a twin pair 7 to 18 years of age. Telephone screening interviews for ADHD symptoms were completed for 5007 families. Diagnostic assessments were administered to 564 families with at least one twin meeting screening criteria, plus 183 control families. Prevalence and age of onset for both ADHD nosologies were calculated by sex and zygosity from parent report data. The prevalence of any DSM-IV ADHD was 6.2% overall, 7.4% in boys and 3.9% in girls. The inattentive subtype was most common in boys; the combined subtype was most common in girls. The mean age of onset of symptoms in children with any DSM-IV ADHD was 3.5 years, with no significant differences between boys and girls. Prevalences of latent class defined ADHD subtypes also varied by sex with the severe inattentive and combined classes more common in boys than girls. The age of onset of symptoms did not differ between boys and girls but were higher than in the DSM-IV subtypes. Findings in this twin sample showed that clinically significant ADHD, defined by either DSM-IV or latent class criterion, has an early age of onset and is more common in boys than girls. As clinical samples are most commonly composed of male combined subtypes, the inattentive subtype of both sexes in the general population is an under- treated segment of the general population.
Telomere Length Among the Elderly and Oldest-Old
Authors: Bischoff Claus , Graakjaer Jesper , Petersen Hans Christian , Jeune Bernard , Bohr Vilhelm A. , Koelvraa Steen , Christensen Kaare 
Published: May 2007

AbstractHuman chromosomes terminate in a number of repeats of the sequence TTAGGG. At birth, each chromosome end is equipped with approximately 15 kb of telomere sequence, but this sequence is shortened during each cell division. In cell cultures telomere shortening is associated with senescence, a phenomenon that has also been observed in normal adult tissues, indicating that telomere loss is associated with organismal ageing. Previous work has established that the rate of telomere loss in humans is age dependent, and recent work shows a sex-specific difference in telomere length and shortening in individuals over the age span of 20 to 75 years. Here, terminal restriction fragment lengths on DNA purified from whole blood were measured to examine the mean telomere length in a cross-sectional cohort of 816 Danish individuals of age 73 to 101 years. In this age group, females show a linear correlation between telomere length and age, whereas the pattern tends to be nonlinear (quadratic in age) for males. This difference in telomere length dynamics between the 2 sexes may be caused by several different mechanisms, including differences in selection by mortality, differences in leukocyte population or different telomerase expression pattern.
Comorbidity Between ADHD and Symptoms of Bipolar Disorder in a Community Sample of Children and Adolescents
Authors: Reich Wendy , Neuman Rosalind J. , Volk Heather E. , Joyner Cynthia A. , Todd Richard D. 
Published: May 2007

AbstractThe prevalence and frequency of comorbidity of possible bipolar disorder was examined with attention-deficit hyperactivity disorder (ADHD) in a nonreferred population of twins. Children and adolescents aged 7 to 18 years with a history of manic symptoms were identified from a population-based twin sample obtained from state birth records (n = 1610). The sample was enriched for ADHD; however, there was also a random control sample (n = 466), which allowed a look at the population prevalence of the disorder. Juveniles with threshold or below threshold manic episodes were further assessed for comorbidity with Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association, 1994) and population-defined ADHD subtypes (from latent class analysis) using Fisher's exact test. Nine juveniles who exhibited DSM-IV manic (n = 1), hypomanic (n = 2) or below threshold episodes (n = 6) were identified. The population prevalence of broadly defined mania in the random sample was 0.2%. The possible manic episodes showed significant comorbidity with population-defined severe combined and talkative ADHD subtypes. It can be concluded that there is a significant association of bipolar symptoms with two population-defined subtypes of ADHD. Episodes of possible bipolar disorders as defined by DSM-IV are uncommon in this nonreferred sample. Children and adolescents with ADHD appear to be only modestly at increased risk for bipolar disorders.
Genetic Contributions to Subtypes of Aggression
Authors: Ligthart Lannie , Bartels Meike , Hoekstra Rosa A. , Hudziak James J. , Boomsma Dorret I. 
Published: May 2007

AbstractBoys and girls may display different styles of aggression. The aim of this study was to identify subtypes of aggression within the Child Behavior Checklist (CBCL) aggression scale, and determine their characteristics for both sexes. Maternal CBCL ratings of 7449 7-year-old twin pairs were analyzed using principal components analyses to identify sub- types of aggression, and structural equation modeling to carry out genetic analyses. Two aggression subtypes were identified: relational and direct aggression. The correlation between these subtypes was .58 for boys and .47 for girls. Boys had higher mean scores for both subtypes of aggression, but sex differences were largest for direct aggression. For relational aggression, 66% of the variance was due to additive genetic influences, 16% to shared environment and 18% to nonshared environment. For direct aggression, additive genetic effects accounted for 53% of the variance in males and 60% in females, shared environment explained 23% of the variance in males and 13% in females, and nonshared environmental effects explained 24% of the variance in males and 27% in females. Covariance between the aggression subtypes was mostly accounted for by additive genetic (55% for boys, 58% for girls) and shared environmental influences (33% for boys, 30% for girls). Direct and relational aggression were both influenced by one underlying set of shared environmental factors, but only partly by the same genes (the genetic correlation was .54 for boys and .43 for girls). These findings may have implications for how aggressive behavior should be assessed in boys and girls.
Limitations of DSM-IV Operationalizations of Alcohol Abuse and Dependence in a Sample of Australian Twins
Authors: Lynskey Michael T. , Nelson Elliot C. , Neuman Rosalind J. , Bucholz Kathleen K. , Madden Pamela A. F. , Knopik Valerie S. , Slutske Wendy , Whitfield John B. , Martin Nicholas G. , Heath Andrew C. 
Published: May 2007

AbstractAlcohol abuse and dependence are among the most common psychiatric conditions identified in epidemiological surveys of the general population. The aim of this article is to examine the psychometric properties of Diagnostic and Statistical Manual of Mental Disorders, (4th ed.; DSM-IV; American Psychiatric Association, 1994) criteria for alcohol abuse and dependence using latent class analysis (LCA). Six thousand two hundred and sixty-five young Australian twins (median age 30 years) were interviewed by telephone between 1996 and 2000 using a modified version of the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA). DSM-IV symptoms of alcohol abuse and dependence were collected by structured diagnostic interview and analyzed using methods of LCA. LCA revealed a 4-class solution for women that classified individuals according to the severity of their alcohol- related problems: no/few problems (66.5%), heavy drinking (23.9%), moderate dependence (7.6%) and severe dependence (2.0%). Among men the preferred solution included 5 classes corresponding to no/few problems (46.4%), heavy drinking (34.3%), moderate dependence (12.2%), severe dependence (3.0%) and abuse (4.0%). Evidence of a male-specific class of alcohol-related problems corresponding to abuse partially supports the DSM conceptualization of alcohol use disorders but suggests that this conceptualization — and measurement — may need to be refined for women. Identification of a male- specific abuse class also has important implications for interventions and treatment as these individuals experienced significant alcohol-related problems and comprised approximately 21% of all men classified with an alcohol use disorder.
Multivariate Genetic Analysis of Academic Skills of the Queensland Core Skills Test and IQ Highlight the Importance of Geneticg
Authors: Wainwright Mark A. , Wright Margaret J. , Luciano Michelle , Geffen Gina M. , Martin Nicholas G. 
Published: May 2007

AbstractThis study examined the genetic and environmental relationships among 5 academic achievement skills of a standardized test of academic achievement, the Queensland Core Skills Test (QCST; Queensland Studies Authority, 2003a). QCST participants included 182 monozygotic pairs and 208 dizygotic pairs (mean 17 years ± 0.4 standard deviation). IQ data were included in the analysis to correct for ascertainment bias. A genetic general factor explained virtually all genetic variance in the component academic skills scores, and accounted for 32% to 73% of their phenotypic variances. It also explained 56% and 42% of variation in Verbal IQ and Performance IQ respectively, suggesting that this factor is genetic g. Modest specific genetic effects were evident for achievement in mathematical problem solving and written expression. A single common factor adequately explained common environmental effects, which were also modest, and possibly due to assortative mating. The results suggest that general academic ability, derived from genetic influences and to a lesser extent common environmental influences, is the primary source of variation in component skills of the QCST.
Genetic and Environmental Influences on the Handedness and Footedness in Japanese Twin Children
Authors: Ooki Syuichi 
Published: May 2007

AbstractThe purpose of this study was to examine the genetic contribution to handedness and footedness in childhood using one of the largest available databases of Japanese twins. The participants were 1131 twin pairs, 1057 males and 1205 females, of 11 or 12 years of age (6th grade of secondary school in the Japanese education system). All data were gathered by questionnaire. The prevalence of left (nonright) handedness was 15% in males and 13% in females. The prevalence of left (nonright) footedness was 13% in males and 11% in females. The similarities between twin pairs, estimated by concordance rates and tetrachoric correlations, suggested a slight genetic effect on male handedness, no genetic effect on female handedness, and no genetic effect on footedness in either sex. Structural equation modeling showed small genetic factors (11%) in male handedness and no genetic factors in female handedness. As to footedness, no genetic factors were observed in either sex. The effects of nonshared environmental factors were large (85%) in males and moderate (44%) in females. Moreover, handedness and footedness tended to be concordant irrespective of sex, with polychoric correlations overr= .70. The results of bivariate genetic analyses were not necessarily satisfactory. For males, no model fit. For females, shared and nonshared environmental factors explained the concordance of handedness and footedness. It was concluded that the genetic effects on handedness and footedness are relatively small, as is their association; moreover, considerably large twin samples are needed to obtain stable and appropriate results.