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At least 199 records · Page 11Linked to original sources
PubMed2004

Psychotic symptoms in pediatric bipolar disorder.

BACKGROUND: There is under-recognition or misdiagnosis of pediatric bipolar disorder with psychotic features. It is of major public health importance to recognize psychosis in bipolar disorder. METHOD: Original research on phenomenological description of psychosis and external validators including family history, longitudinal course and treatment effects are systematically reviewed. Age differences, sampling, and interview methods of the studies on pediatric bipolar disorder that reported psychotic features are compared. Critical differentiating features between pediatric bipolar disorder and pediatric schizophrenia are summarized given the presence of overlapping psychotic features. RESULTS: Prevalence of psychotic features in pediatric bipolar disorder ranged from 16 to 87.5% based on age and methodological differences. The most common psychotic features are mood congruent delusions, mainly grandiose delusions. Psychotic features appear in the context of affective symptoms in pediatric bipolar disorder as opposed to schizophrenia where psychotic symptoms are independent of them. Family history of affective psychosis aggregated in probands with bipolar disorder. LIMITATIONS: There is discrepancy in clinical appraisal of what constitutes psychosis and pediatric bipolar disorder, apart from the differences in methodology and nature of the samples. CONCLUSION: Clinicians must be vigilant in identifying psychosis in pediatric bipolar disorder, especially when there is a positive family history of psychosis.

Adolescent↗
PubMed2004

Multivariate QTL linkage analysis suggests a QTL for platelet count on chromosome 19q.

Platelet count is a highly heritable trait with genetic factors responsible for around 80% of the phenotypic variance. We measured platelet count longitudinally in 327 monozygotic and 418 dizygotic twin pairs at 12, 14 and 16 years of age. We also performed a genome-wide linkage scan of these twins and their families in an attempt to localize QTLs that influenced variation in platelet concentrations. Suggestive linkage was observed on chromosome 19q13.13-19q13.31 at 12 (LOD = 2.12, P = 0.0009), 14 (LOD = 2.23, P = 0.0007) and 16 (LOD = 1.01, P = 0.016) years of age and multivariate analysis of counts at all three ages increased the LOD to 2.59 (P = 0.0003). A possible candidate in this region is the gene for glycoprotein VI, a receptor involved in platelet aggregation. Smaller linkage peaks were also seen at 2p, 5p, 5q, 10p and 15q. There was little evidence for linkage to the chromosomal regions containing the genes for thrombopoietin (3q27) and the thrombopoietin receptor (1q34), suggesting that polymorphisms in these genes do not contribute substantially to variation in platelet count between healthy individuals.

Adolescent↗
PubMed2000

Longitudinal evaluation of activated protein C resistance among normal pregnancies of Hispanic women.

OBJECTIVE: This study was undertaken to describe pregnancy-associated activated protein C resistance and the presence of the factor V Leiden mutation in a sample population of pregnant Hispanic women. STUDY DESIGN: Twenty healthy Hispanic women with single intrauterine pregnancies were randomly selected. Blood samples were taken before 8 weeks' gestation, every 4 weeks during pregnancy, and at 6 weeks post partum. Samples were collected, separated, and stored at -70 degrees C until assay. Standard and modified partial thromboplastin time-based assays were used to evaluate response to activated protein C. A sensitivity ratio < or =2 indicated resistance to activated protein C. Repeated measures analysis of variance and unpaired t tests were used as appropriate. P <.05 was considered significant. RESULTS: Mean (+/-SEM) maternal age was 29 +/- 5 years, and most women were multiparous. Mean gestational age at delivery was 38 weeks' gestation, and the mean birth weight was 3000 g. According to the standard assay, 10 women (50%) acquired activated protein C resistance by 13 weeks' gestation, and this condition persisted through delivery and resolved post partum. Another two had preexisting activated protein C resistance. Results of the standard assay were significantly different for women with preexisting and pregnancy-associated activated protein C resistance (1.55 vs 2.18; P =.01). The modified assay distinguished between women with preexisting and pregnancy-associated activated protein C resistance at 8 weeks' gestation, 24 weeks' gestation, and post partum. The pregnancies of the women with preexisting activated protein C resistance were complicated by oligohydramnios at 34 weeks' gestation and required delivery at 36 weeks' gestation. One infant was small for gestational age. Allele-specific polymerase chain reaction analysis demonstrated that both patients with preexisting activated protein C resistance carried one copy of the factor V Leiden mutation. CONCLUSION: The incidences of pregnancy-associated and factor V Leiden mutation-associated activated protein C resistances in our cohort of gravid Hispanic women was higher than previously reported. Factor V Leiden-associated activated protein C resistance in two patients was associated with adverse perinatal outcome.

Adult↗
PubMed2004

Genetic and environmental contributions to stability and change of ADHD symptoms between 8 and 13 years of age: a longitudinal twin study.

OBJECTIVE: To study the genetic and environmental contributions to stability and change of attention-deficit/hyperactivity disorder (ADHD) symptoms between 8 and 9 and 13 and 14 years of age. METHOD: The sample included 1,480 twin pairs born in Sweden between May 1985 and December 1986. At wave 1 in 1994, when twins were 8-9 years old, 1,106 (75%) of the parents responded to a mailed questionnaire, and at wave 2 when the twins were 13-14 years old, 1,063 (73%) responded. A checklist with 14 items based on the 14 DSM-III-R symptoms for ADHD was completed. Structural equation modeling was used to analyze the data. RESULTS: A relatively high stability of ADHD symptoms over this 5-year period was found. This continuity was mainly due to the same genetic effects operating at both points in time. Change in symptoms between childhood and early adolescence was to a large extent due to new genetic effects in early adolescence but also due to new nonshared environmental effects that became important during adolescence. CONCLUSIONS: The genetic stability highlights the importance of the continuing search for genes and endophenotypes of ADHD.

Adolescent↗
PubMedDate not supplied

Genetic influences in different aspects of language development: the etiology of language skills in 4.5-year-old twins.

The genetic and environmental etiologies of diverse aspects of language ability and disability, including articulation, phonology, grammar, vocabulary, and verbal memory, were investigated in a U.K. sample of 787 pairs of 4.5-year-old same-sex and opposite-sex twins. Moderate genetic influence was found for all aspects of language in the normal range. A similar pattern was found at the low end of the distribution with the exception of two receptive measures. Environmental influence was mainly due to nonshared factors, unique to the individual, with little influence from shared environment for most measures. Genetic and environmental influences on language ability and disability are quantitatively and qualitatively similar for males and females.

Child, Preschool↗
PubMedDate not supplied

Revisiting the association between reading achievement and antisocial behavior: new evidence of an environmental explanation from a twin study.

Previous studies have reported, but not explained, the reason for a robust association between reading achievement and antisocial behavior. This association was investigated using the Environmental Risk (E-Risk) Longitudinal Twin Study, a nationally representative 1994-1995 birth cohort of 5- and 7-year-olds. Results showed that the association resulted primarily from environmental factors common to both reading and antisocial behavior and was stronger in boys. Environmental factors also explained the relation between reading disability and conduct disorder. Leading candidate environmental risk factors weakly mediated the association. For boys the best explanation was a reciprocal causation model: poor reading led to antisocial behavior, and vice versa. In contrast, the relation between reading achievement and attention deficit hyperactivity disorder was best explained by common genetic influences.

Adolescent↗
PubMed1998

Longitudinal study of Escherichia coli O157:H7 dissemination on four dairy farms in Wisconsin.

A 14-month longitudinal study was conducted on four dairy farms (C, H, R, and X) in Wisconsin to ascertain the source(s) and dissemination of Escherichia coli O157:H7. A cohort of 15 heifer calves from each farm were sampled weekly by digital rectal retrieval from birth to a minimum of 7 months of age (range, 7 to 13 months). Over the 14 months of the study, the cohort heifers and other randomly selected cattle from farms C and H tested negative. Farm R had two separate periods of E. coli O157:H7 shedding lasting 4 months (November 1995 to February 1996) and 1 month (July to August 1996), while farm X had at least one positive cohort animal for a 5-month period (May to October 1996). Heifers shed O157:H7 strains in feces for 1 to 16 weeks at levels ranging from 2.0 x 10(2) to 8.7 x 10(4) CFU per g. E. coli O157:H7 was also isolated from other noncohort cattle, feed, flies, a pigeon, and water associated with the cohort heifers on farms R and/or X. When present in animal drinking water, E. coli O157:H7 disseminated through the cohort cattle and other cattle that used the water source. E. coli O157:H7 was found in water at < 1 to 23 CFU/ml. Genomic subtyping by pulsed-field gel electrophoresis demonstrated that a single O157:H7 strain comprised a majority of the isolates from cohort and noncohort cattle, water, and other positive samples (i.e., from feed, flies, and a pigeon, etc.) on a farm. The isolates from farm R displayed two predominant XbaI restriction endonuclease digestion profiles (REDP), REDP 3 and REDP 7, during the first and second periods of shedding, respectively. Six additional REDP that were > or = 89% similar to REDP 3 or REDP 7 were identified among the farm R isolates. Additionally, the REDP of an O157:H7 isolate from a heifer on farm R in 1994 was indistinguishable from REDP 3. Farm X had one O157:H7 strain that predominated (96% of positive samples had strains with REDP 9), and the REDP of an isolate from a heifer in 1994 was indistinguishable from REDP 9. These results suggest that E. coli O157:H7 is disseminated from a common source on farms and that strains can persist in a herd for a 2-year period.

Animal Husbandry↗
PubMed1996

Variation in metabolic enzyme activity of persistent Haemophilus influenzae in respiratory tracts of patients with cystic fibrosis.

Haemophilus influenzae organisms were isolated from sputum specimens prospectively collected from 40 patients with cystic fibrosis during 2 years to study variations in the metabolic enzyme activities of persistent H. influenzae strains as determined by biotyping. In total, 97 distinct H. influenzae strains without variations in their major outer membrane protein (MOMP) patterns and 73 MOMP variants derived from 30 of these distinct strains were obtained. Twelve distinct strains and 42 MOMP variant strains were isolated at multiple time points during the study period, indicating the persistence of these strains. Among the 54 persistent H. influenzae strains, 22 (41%) strains with stable MOMP compositions showed random variations in biotypes. In 39 of 103 (38%) H. influenzae strains, biotype changes coincided with MOMP variations. Biotype variations were the result of both the loss and the acquisition of enzyme activities. The results of the study indicate that changes in metabolic enzyme activity occur randomly during the persistence of H. influenzae organisms in cystic fibrosis patients, irrespective of MOMP variations.

Cystic Fibrosis↗
PubMed1998

Evolution of syncytium-inducing and non-syncytium-inducing biological virus clones in relation to replication kinetics during the course of human immunodeficiency virus type 1 infection.

To investigate the temporal relationship between human immunodeficiency virus type 1 (HIV-1) replicative capacity and syncytium-inducing (SI) phenotype, biological and genetic characteristics of longitudinally obtained virus clones from two HIV-1-infected individuals who developed SI variants were studied. In one individual, the emergence of rapidly replicating SI and non-syncytium-inducing (NSI) variants was accompanied by a loss of the slowly replicating NSI variants. In the other subject, NSI variants were always slowly replicating, while the coexisting SI variants showed an increase in the rate of replication. Irrespective their replicative capacity, the NSI variants remained present throughout the infection in both individuals. Phylogenetic analysis of the V3 region showed early branching of the SI variants from the NSI tree. Successful SI conversion seemed a unique event since no SI variants were found among later-stage NSI variants. This was also confirmed by the increasing evolutionary distance between the two subpopulations. At any time point during the course of the infection, the variation within the coexisting SI and NSI populations did not exceed 2%, indicating continuous competition within each viral subpopulation.

Amino Acid Sequence↗
PubMed1978

The XYY genotype.

The epidemiological data pertaining to the XYY genotype suggest that there is a three- to fourfold overrepresentation of XYY individuals in mental and penal settings and a twentyfold overrepresentation of mental-penal (special security) settings. The reasons behind the risk for behavioral disability are not known at this time. Tallness and ondulocystic acne are reported frequently to be associated with the genotype. Since much of the available information about the XYY sex chromosome complement is biased, more data is required before definitive statements can be made about the personality characteristics or intelligence of the vast majority of XYY men not appearing in social settings oriented towards behavioral deviancy.

Abnormalities, Multiple↗
PubMed2004

Genetic influence on inflammation variables in the elderly.

BACKGROUND: Inflammation variables (C-reactive protein [CRP], fibrinogen, and soluble intercellular adhesion molecule-1 [sICAM-1]) have been identified as risk factors for cardiovascular disease. It is still not known how much the regulation of inflammatory risk factors is determined by genetic factors, and the aim of this study was to determine the heritability of these inflammation variables and of the acute phase regulating cytokines interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) at older ages. METHODS AND RESULTS: The heritability of CRP, fibrinogen, sICAM-1, IL-6, and TNF-alpha was determined in a twin study consisting of 129 monozygotic twin pairs and 153 dizygotic same-sex twins aged 73 to 94 years who participated in the Longitudinal Study of Aging of Danish Twins. Furthermore, we determined the influence of selected genetic polymorphisms on the plasma level variations. Genetic factors accounted for 20% to 55% of the variation in plasma levels of the inflammation variables. The highest heritability was found for sICAM-1. The genetic polymorphisms we studied explained only a small, insignificant part of the heritability. CONCLUSIONS: This study in elderly twins provides evidence for a substantial genetic component of inflammatory cardiovascular risk factors among the elderly.

Acute-Phase Proteins↗
PubMed2004

Alzheimer's disease, genes, and environment: the value of international studies.

OBJECTIVE: To describe the construction of a disease model incorporating both genetic an environmental factors in the etiology of Alzheimer's disease (AD), using data generated from the Indianapolis-Ibadan dementia project (I-IDP). METHOD: The I-IDP is a longitudinal comparative study of the prevalence and incidence o dementia in 2 communities: elderly African Americans living in Indianapolis, Indiana, an Yoruba living in Ibadan, Nigeria. RESULTS: African Americans are more than twice as likely as Yoruba to develop AD. Possible explanations for this finding include genetic factors: the possession of the apolipoprotein E epsilon4 allele does not increase risk for AD among Yoruba but confers a sligh increase in AD risk for African Americans. As well, environmental factors may play a role: African Americans have a higher risk of vascular risk factors than do Yoruba. CONCLUSIONS: International comparative studies, particularly those involving population from developing and developed countries, offer a unique opportunity for applying new in formation regarding population genetics to traditional AD risk factor research.

Aged↗
PubMed2003

Power of linkage analysis using traits generated from simulated longitudinal data of the Framingham Heart Study.

The Framingham Heart Study is a very successful longitudinal research for cardiovascular diseases. The completion of a 10-cM genome scan in Framingham families provided an opportunity to evaluate linkage using longitudinal data. Several descriptive traits based on simulated longitudinal data from the Genetic Analysis Workshop 13 (GAW13) were generated, and linkage analyses were performed for these traits. We compared the power of detecting linkage for baseline and slope genes in the simulated data of GAW13 using these traits. We found that using longitudinal traits based on multiple follow-ups may not be more powerful than using cross-sectional traits for genetic linkage analysis.

Adult Children↗
PubMed2004

PROP1 mutations cause progressive deterioration of anterior pituitary function including adrenal insufficiency: a longitudinal analysis.

Mutations in the PROP1 gene are the most frequent genetic defects in patients with combined pituitary hormone insufficiency. However, controversy exists about the timing and extent of pituitary insufficiency, and it remains unclear whether adrenal failure is a typical feature of this condition. We performed a retrospective longitudinal analysis of nine patients with PROP1 mutations who were under medical supervision at our clinic for 15.7 +/- 3.4 yr. All patients initially presented with growth failure (height sd score, -3.7 +/- 0.3) at a mean age of 4.9 +/- 0.8 yr. They were first diagnosed with GH and TSH deficiency, and replacement therapy was instituted at 6.1 +/- 1.1 and 6.8 +/- 1.2 yr, respectively. All seven patients who reached pubertal age required sex hormone substitution at 15.0 +/- 0.7 yr. Repeated functional testing of the anterior pituitary axes revealed a progressive decline with age in peak levels of GH, TSH, prolactin, and LH/FSH. All patients developed at least partial adrenal insufficiency, with a gradual decline of the function of the pituitary adrenal axis and eventually required substitution with hydrocortisone at a mean age of 18.4 +/- 3.5 yr. It is concluded that anterior pituitary function in patients with PROP1 mutations deteriorates progressively and includes adrenal insufficiency as a feature of this condition, which has important clinical relevance in childhood and adolescence.

Adolescent↗
PubMed2001

Clinical markers of early disease in persons near onset of Huntington's disease.

OBJECTIVE: There is increasing evidence that neuron loss precedes the phenotypic expression of Huntington's disease (HD). As genes for late-onset neurodegenerative diseases are identified, the need for accurate assessment of phenoconversion (i.e., the transition from health to the disease phenotype) will be important. METHODS: Prospective longitudinal evaluation using the Unified Huntington's Disease Rating Scale (UHDRS) was conducted by Huntington Study Group members from 36 sites. There were 260 persons considered "at risk" for HD who initially did not have manifest disease and had at least one subsequent evaluation. Repeat UHDRS data, obtained an average of 2 years later, showed that 70 persons were given a diagnosis of definite HD based on the quantified neurologic examination. RESULTS: Baseline cognitive performances were consistently worse for the at-risk group who demonstrated conversion to a definitive diagnosis compared with those who did not. Longitudinal change scores showed that the at-risk group who did not demonstrate manifest disease during the follow-up study period demonstrated improvements in all cognitive tests, whereas performances in the at-risk group demonstrating conversion to disease during the study declined across cognitive domains. CONCLUSIONS: Neuropsychological measures show impairment 2 years before the development of more manifest motor disease. Findings suggest that these brief cognitive measures administered over time may capture early striatal neural loss in HD.

Adult↗
PubMed2006

Efficacy of retrospective recall of attention-deficit hyperactivity disorder symptoms: A twin study.

Attention-deficit hyperactivity disorder (ADHD) is currently recognized as a neurobiological, genetically based disorder in both children and adults. In this article we examine whether, by using a sample of middle-aged male twin veterans, the phenotypic characterization, prevalence, heritability and the longitudinal course of the illness is comparable to results observed in samples of children and adolescents. We evaluated the utility of adult reports of lifetime ADHD symptoms by examining the heritability of retrospectively reported childhood symptoms, using both symptom-based and discrete classification-based approaches, as well as examining the persistence of ADHD symptoms into adulthood for that subsample of individuals who were judged to possibly have ADHD as children. Our results showed prevalence rates that were approximately similar to those observed in other studies, demonstrable familiality, similar item endorsement patterns, a strong genetic association between hyperactive and inattentive subtypes, and a longitudinal decline in symptom severity. We concluded that while assessing ADHD in adult probands may be less accurate than with children or adolescents, since it demonstrates several characteristics in common with other assessment techniques it remains a viable diagnostic and research strategy, even with population samples.

Adult↗
PubMed2003

[Identification of immunological effector cells after autologous cytokine-induced killer cells treatment and its clinical implication in hepatocellular carcinoma patients].

OBJECTIVE: To investigate the alteration of the cellular profiles of T lymphocyte subsets and dendritic cell subsets in peripheral blood of primary hepatocellular carcinoma (HCC) patients after being transfused with autologous cytokine-induced killer cells (CIK) in patients, then to evaluate the clinical efficacy of the immune therapeutic strategy. METHODS: Peripheral blood mononuclear cells (PBMCs) from 13 patients with primary were collected using blood cell separator, and expanded in the fresh AIM-V medium in the presence of cytokine cocktail including interferon-gamma (IFN-gamma), monoclonal antibody (mAb) against CD3 and interleukin-2 (IL-2). The phenotypic patterns of CIK cells were longitudinally characterized by flow cytometry on day 0, 4, 7, 10,13 and 15 during the incubation period. PBMCs obtained from HCC patients before or after CIK cells transfusion into bodies to assay the changes of proportion of DC1 or DC2 in peripheral blood. RESULTS: After in vitro incubation for 14 or 15 days, a large of CD3(+)CD56(+) cells were produced from their progenitors and the percentages of CD3(+)CD8(+), CD3(+)CD56(+), CD25(+) cells significantly increased from 33.5% +/- 10.1%, 7.7% +/- 2.8%, and 12.3% +/- 4.5% at the beginning to 36.6% +/- 9.0% (P < 0.05), 18.9% +/- 6.9% (P < 0.01), and 16.4% +/- 5.9% (P < 0.05) at the day 15, respectively. In contrast, the percentages of CD3(+)CD4(+) and NK cells displayed no significant difference. The percentages of CD3(+), CD3(+)CD8(+) cells was held at a higher level during the whole incubation period, however those of the CD25(+), and CD3(+)CD56(+) cells began decreasing on day 7 and day 13, respectively. The proportion of type I of dendritic cells (DC1) and type II of dendritic cells (DC2) subsets increased from 0.59% +/- 0.23% and 0.26% +/- 0.12% before CIK cell transfusion to 0.85% +/- 0.27% and 0.43% +/- 0.20% (all P < 0.01) after CIK cell transfusion. The symptom of HCC patients receiving the CIK cell therapy was markedly ameliorated, and not side effect was seen in the treatment. CONCLUSION: Our results indicated that autologous CIK cells is able to boost the cellular immunological function in HCC patients, which probably provide a potent immune therapeutic strategy for HCC patients.

Adult↗