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PubMed1993

The worksite component of variance: design effects and the Healthy Worker Project.

Variance estimates in worksite health promotion studies depend partly on the intraclass correlation coefficient (ICC). ICC quantifies homogeneity of a variable within worksites. ICC would be zero for randomly formed worksites, but is generally positive because employees tend to share personal characteristics. The ratio comparing the variance estimated from worksite means with that estimated from individuals under simple random sampling is the design effect (DEFF). A DEFF of 1.0 indicates no excess variance due to worksite. The Healthy Worker Project (HWP) was a 32 worksite cross-sectional and longitudinal study of a weight and smoking intervention program. ICCs in cross-sectional surveys for health-related outcome variables ranged from 0.006 to 0.009, DEFFs from 2.0 to 2.6 ICCs/DEFF's in longitudinal analysis were smaller; ICCs ranged from -0.002 to 0.003, DEFFs from 0.7 to 1.5. Positive ICCs substantially increased variance estimates at a single measurement, yet variance of longitudinal analysis was less subject to worksite dependence. It is concluded the worksite component of variance is real and should not be ignored, although the worksite component of variance is small in these longitudinal analyses. This observation should be replicated before it is used in other worksite health promotion research.

Analysis of Variance↗

PubMed1980

Primary presenting problem and mental health service delivery.

This study describes the variety of problems reported by clients seeking the services of a large urban community mental health center and explores the extent to which these problems are related to three sets of variables: client demographic characteristics, system entry, and system response. A 10% random sample totaling 273 case files was examined. The most frequently reported problem area was interpersonal followed by drug/alcohol abuse and cognitive disturbance. Clients' presenting problem was significantly related to all three sets of variables. Implications for planning service delivery are discussed with emphasis on identifying both unique and shared center responses to presenting problems, client characteristics, and system entry factors.

Catchment Area, Health↗

PubMed1995

Characterisation of Haemophilus influenzae proteins by two-dimensional gel electrophoresis.

The proteins of nontypable and type b Haemophilus influenzae isolates were characterised using two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). Coomassie Brilliant. Blue R-250 was used for protein detection. Two hundred and twenty eight proteins were resolved from whole cell lysates prepared from a standard nontypable H. influenzae strain (designated HI-64443) when isoelectric focusing was used for the first-dimensional separation of 2-D PAGE. When nonequilibrium pH gel electrophoresis (NEPHGE) was used to separate basic proteins in the first dimension, 50 proteins were detected for HI-64443; 20 of the basic proteins detected were considered to be unique for this separation protocol. The apparent molecular weights and isoelectric points were determined for 82 of the proteins resolved for HI-64443. The variation of the proteins from the standard bacterial strain (HI-64443) was determined for nontypable H. influenzae isolates. On the basis of their electrophoretic mobilities, 17.5% of the proteins of HI-64443 were shared by four other nontypable H. influenzae strains analysed. These data identified both conserved and variable proteins among the nontypable H. influenzae isolates analysed. The results obtained indicated that 2-D PAGE was able to discriminate nontypable H. influenzae into population clones identified by other procedures. The 2-D protein profiles obtained for type b H. influenzae strains were similar to those obtained for nontypable H. influenzae strains. The extent of the protein variation observed between type b and nontypable H. influenzae strain was similar to that observed among nontypable strains alone. These data are discussed in relation to the application of 2-D PAGE as a tool for studies on bacterial epidemiology and for the analysis of the genome structure and gene expression of Haemophilus influenzae.

Bacterial Proteins↗

PubMed1994

Human corpus callosum: a stable mathematical model of regional neuroanatomy.

The functional utility of regional parameters of the corpus callosum (CC) derived from factor analysis has been demonstrated in the rat and the human. In this study, we have utilized factor analysis to compare CC structure between two independent groups of human subjects. Tracings of the CC were taken from the midsagittal MRIs of two human samples consisting of 103 healthy volunteers and 146 neurological patients. CCs were digitized and factor analyses were performed on 99 widths, area, axis length, and perimeter. The factor structures of these two data sets were highly congruent except that one factor analysis yielded a seven-factor solution, whereas the factor analysis of the other subject population gave six factors. Further study determined that the six-factor structure could be attributed to the presence of non-consistent right-handed males whose wider CCs in the isthmus region biased the correlations. When CC parameters of consistent and non-consistent right-handed subjects were standardized, a seven-factor structure resulted. Reproducibility of the factor structure indicates that there are shared neuroanatomical characteristics of CC morphology among two disparate populations of humans in spite of variability in CC size due to sex, age, hand preference, and hand consistency.

Adolescent↗

PubMed2000

Ligand-binding sites in Ig-like domains of receptor tyrosine kinases.

Receptor tyrosine kinases are cell-bound, membrane-spanning receptors that transduce growth factor dependent signals to the intracellular environment. Their catalytic cytoplasmic domains share a high level of sequence similarity, but their extracellular portions usually have a highly variable, multiple-domain structure. In a growing number of cases immunoglobulin-like domains contained within the extracellular portion have been shown to contain the ligand-binding site. In recent years experimental three-dimensional structures have been determined for some of these domains, free or in complex with their ligand. Here we review current structural information on these immunoglobulin-like domains and the growth factors that bind to them, with an emphasis on the vascular endothelial growth factor, nerve growth factor, and fibroblast growth factor systems.

Amino Acid Sequence↗

PubMed2006

Characterization of expressed Pgip genes in rice and wheat reveals similar extent of sequence variation to dicot PGIPs and identifies an active PGIP lacking an entire LRR repeat.

Polygalacturonase-inhibiting proteins (PGIPs) are leucine-rich repeat (LRR) proteins involved in plant defence. A number of PGIPs have been characterized from dicot species, whereas only a few data are available from monocots. Database searches and genome-specific cloning strategies allowed the identification of four rice (Oryza sativa L.) and two wheat (Triticum aestivum L.) Pgip genes. The rice Pgip genes (Ospgip1, Ospgip2, Ospgip3 and Ospgip4) are distributed over a 30 kbp region of the short arm of chromosome 5, whereas the wheat Pgip genes, Tapgip1 and Tapgip2, are localized on the short arm of chromosome 7B and 7D, respectively. Deduced amino acid sequences show the typical LRR modular organization and a conserved distribution of the eight cysteines at the N- and C-terminal regions. Sequence comparison suggests that monocot and dicot PGIPs form two separate clusters sharing about 40% identity and shows that this value is close to the extent of variability observed within each cluster. Gene-specific RT-PCR and biochemical analyses demonstrate that both Ospgips and Tapgips are expressed in the whole plant or in a tissue-specific manner, and that OsPGIP1, lacking an entire LRR repeat, is an active inhibitor of fungal polygalacturonases. This last finding can contribute to define the molecular features of PG-PGIP interactions and highlights that the genetic events that can generate variability at the Pgip locus are not only limited to substitutions or small insertions/deletions, as so far reported, but can also involve variation in the number of LRRs.

Amino Acid Sequence↗

PubMed2006

Occurrence of two different types of RNA-5-containing beet necrotic yellow vein virus in the UK.

Two types of RNA-5-containing beet necrotic yellow vein virus (BNYVV) have been detected in the UK at different sites in Norfolk. On the basis of nucleotide (nt) sequence comparisons, one virus source (UK-MH) was clearly identified as P type BNYVV, a virus type that had previously only been detected in two widely separated parts of the world, France and Kazakhstan. The other virus source (UK-FF) has a complex genome composition. The analysed portions of its RNAs 2 and 4 are closely related to the corresponding portions in the RNAs of the East Asian A type isolate S, whereas those of its RNAs 1 and 3 resemble P type RNA 1 from Kazakhstan and European A type RNA 3, respectively. Interestingly, the P25 encoded on its RNA 3 has an unique TYHG tetrad in the highly variable amino acid positions 67-70. RNA 5 of the UK-FF BNYVV source shares properties with P type RNA 5, but also with East Asian types of RNA 5. The possible origin and epidemiology of BNYVV types is discussed.

Base Sequence↗

PubMed1993

Molecular cloning of the mouse equivalent of CD9 antigen.

The CD9 antigen was originally described as a 24 kDa molecule present on B lineage-derived acute lymphoblastic leukemia cells and developing B-lymphocytes. However, platelets express a large amount of CD9 antigen and can be activated by CD9 antibodies. We report here the cloning and sequencing of a cDNA coding for the mouse CD9 antigen. There is 89% homology at amino acid level between the human and mouse CD9 molecules. Most of the differences (19 out of 24) are located in the large putative extracellular domain encoded by exons 5 and 6. CD9 antigen belongs to a new cell surface protein family which includes TAPA1 and the platelet activation antigen CD63. These proteins share common structural features with the CD9 antigen and a similar distribution of the evolutionarily variable region.

Amino Acid Sequence↗

PubMed1987

Familial aggregation in physical fitness, coronary heart disease risk factors, and pulmonary function measurements.

In order to test for the presence of familial aggregation in physical fitness and coronary heart disease risk factors, body fat, submaximal power output, muscular strength, muscular endurance, blood pressure, pulmonary functions, and several blood biochemical variables were measured in 304 nuclear families living in the Quebec city area. Analysis of variance indicated a larger between-family than within-family variation for all the variables. When all members of nuclear families were considered, intraclass correlations ranged from 0.21 to 0.34 (P less than or equal to 0.01). Interclass correlations computed for various pairs of relatives revealed significant parent-child and sibling correlations for all the variables (0.14 less than or equal to r less than or equal to 0.55; P less than or equal to 0.01). On the other hand, spousal correlations tended to be lower but significant (0.10 less than or equal to r less than or equal to 0.30; P less than or equal to 0.05) for all variables except subcutaneous fat and hemoglobin concentration. These results suggest that heredity and common lifestyle shared by members of nuclear families are responsible for the familial aggregation of physical fitness, coronary heart disease risk factors, and pulmonary functions. The findings also support the notion of considering the nuclear family as a unit of intervention in the application of preventive measures aimed at the reduction of several risk factors.

Adolescent↗

PubMed2006

Testing the limits of cognitive plasticity in older adults: application to attentional control.

Laboratory based training studies suggest that older adults can benefit from training in tasks that tap control aspects of attention. This was further explored in the present study in which older and younger adults completed an adaptive and individualized dual-task training program. The testing-the-limits approach was used [Lindenberger, U., & Baltes, P. B. (1995). Testing-the-limits and experimental simulation: Two methods to explicate the role of learning in development. Human Development, 38, 349-360.] in order to gain insight into how attentional control can be improved in older adults. Results indicated substantial improvement in overlapping task performance in both younger and older participants suggesting the availability of cognitive plasticity in both age groups. Improvement was equivalent among age groups in response speed and performance variability but larger in response accuracy for older adults. The results suggest that time-sharing skills can be substantially improved in older adults.

Adult↗

PubMed2004

Accounting for depressive symptoms in women: a twin study of associations with interpersonal relationships.

BACKGROUND: This study examined how interpersonal relationships, specifically marital quality and adequacy of social support, are associated with depressive symptoms among women. METHODS: A sample of 326 female monozygotic and dizygotic twin pairs and their spouses was drawn from the Swedish Twin Registry. Associations among the three variables were evaluated by comparing similarities among monozygotic and dizygotic female twin pairs. RESULTS: Interpersonal relationships contributed between 18% and 31% of the variance for depressive symptoms in women. Associations among the three variables were accounted for by genetic influences when women's reports were used. Non-shared environmental influences were important for the association between marital quality and depressive symptoms when a combination of husband and wife reports of marital quality were used. LIMITATIONS: The data is cross-sectional and the generalizability of these findings to depressive symptoms in men or to individuals with major depression is not clear. CONCLUSIONS: These findings indicate important associations among marital quality, social support and depressive symptoms in women, which should be taken into consideration for prevention and intervention strategies targeting depression.

Adult↗

PubMed2006

Cardiac regulation in the socially monogamous prairie vole.

Social experiences, both positive and negative, may influence cardiovascular regulation. Prairie voles (Microtus ochrogaster) are socially monogamous rodents that form social bonds similar to those seen in primates, and this species may provide a useful model for investigating neural and social regulation of cardiac function. Cardiac regulation has not been studied previously in the prairie vole. Radiotelemetry transmitters were implanted into adult female prairie voles under anesthesia, and electrocardiographic parameters were recorded. Autonomic blockade was performed using atenolol (8 mg/kg ip) and atropine methyl nitrate (4 mg/kg ip). Several variables were evaluated, including heart rate (HR), HR variability and the amplitude of respiratory sinus arrhythmia. Sympathetic blockade significantly reduced HR. Parasympathetic blockade significantly increased HR, and reduced HR variability and the amplitude of respiratory sinus arrhythmia. Combined autonomic blockade significantly increased HR, and reduced HR variability and respiratory sinus arrhythmia amplitude. The data indicate that autonomic function in prairie voles shares similarities with primates, with a predominant vagal influence on cardiac regulation. The current results provide a foundation for studying neural and social regulation of cardiac function during different behavioral states in this socially monogamous rodent model.

Analysis of Variance↗

PubMed2025

Human genetic variation reveals FCRL3 is a lymphocyte receptor for Yersinia pestis.

Yersinia pestis is the bacterium responsible for plague, one of the deadliest diseases in history. To discover human genetic determinants of Y. pestis infection, we utilized nearly 1,000 genetically diverse lymphoblastoid cell lines in a cellular genome-wide association study. A nonsynonymous SNP, rs2282284 (N721S), in Fc receptor-like 3 (FCRL3) was associated with bacterial invasion of host cells (p = 9 × 10-8). Overexpressed FCRL3 facilitated attachment and invasion of Y. pestis and colocalized with Y. pestis at attachment sites. These properties were variably conserved across the FCRL family, revealing an immunoglobulin-like domain and signaling motifs shared by FCRL3 and FCRL5 to be necessary for attachment and invasion. Direct binding to FCRL5 extracellular domain was confirmed, and B cells (the primary cells that express FCRLs) were preferentially invaded by Y. pestis. Thus, Y. pestis hijacks FCRL proteins, possibly taking advantage of an immune receptor to create a lymphocyte niche during infection.

Yersinia pestis↗

PubMed2003

Mental models of safety: do managers and employees see eye to eye?

PROBLEM: Disagreements between managers and employees about the causes of accidents and unsafe work behaviors can lead to serious workplace conflicts and distract organizations from the important work of establishing positive safety climate and reducing the incidence of accidents. METHOD AND RESULTS: In this study, the authors examine a model for predicting safe work behaviors and establish the model's consistency across managers and employees in a steel plant setting. Using the model previously described by Brown, Willis, and Prussia (2000), the authors found that when variables influencing safety are considered within a framework of safe work behaviors, managers and employees share a similar mental model. The study then contrasts employees' and managers' specific attributional perceptions. Findings from these more fine-grained analyses suggest the two groups differ in several respects about individual constructs. Most notable were contrasts in attributions based on their perceptions of safety climate. When perceived climate is poor, managers believe employees are responsible and employees believe managers are responsible for workplace safety. However, as perceived safety climate improves, managers and employees converge in their perceptions of who is responsible for safety. IMPACT ON INDUSTRY: It can be concluded from this study that in a highly interdependent work environment, such as a steel mill, where high system reliability is essential and members possess substantial experience working together, managers and employees will share general mental models about the factors that contribute to unsafe behaviors, and, ultimately, to workplace accidents. It is possible that organizations not as tightly coupled as steel mills can use such organizations as benchmarks, seeking ways to create a shared understanding of factors that contribute to a safe work environment. Part of this improvement effort should focus on advancing organizational safety climate. As climate improves, managers and employees are likely to agree more about the causes of safe/unsafe behaviors and workplace accidents, ultimately increasing their ability to work in unison to prevent accidents and to respond appropriately when they do occur. Finally, the survey items included in this study may be useful to organizations wishing to conduct self-assessments.

Accident Prevention↗

PubMed1999

Crystal structures of two Sm protein complexes and their implications for the assembly of the spliceosomal snRNPs.

The U1, U2, U4/U6, and U5 small nuclear ribonucleoprotein particles (snRNPs) involved in pre-mRNA splicing contain seven Sm proteins (B/B', D1, D2, D3, E, F, and G) in common, which assemble around the Sm site present in four of the major spliceosomal small nuclear RNAs (snRNAs). These proteins share a common sequence motif in two segments, Sm1 and Sm2, separated by a short variable linker. Crystal structures of two Sm protein complexes, D3B and D1D2, show that these proteins have a common fold containing an N-terminal helix followed by a strongly bent five-stranded antiparallel beta sheet, and the D1D2 and D3B dimers superpose closely in their core regions, including the dimer interfaces. The crystal structures suggest that the seven Sm proteins could form a closed ring and the snRNAs may be bound in the positively charged central hole.

Amino Acid Sequence↗

PubMed2003

[Arteriovenous malformations of the vein of Galen].

Vein of Galen arteriovenous malformations encompass a diverse group of vascular anomalies that share a common feature: dilatation of the vein of Galen. Although clinical presentations are highly variable, depending on age of presentation, signs and symptoms overlap between age groups. The association of heart failure and cranial bruit constitutes the most striking clinical presentation in neonates. However, less severe and fulminant modes of presentation are frequent in older infants, children, and adults. Treatment approaches consist of symptomatic treatment of heart failure on the one hand and of surgery or endovascular treatment on the other. The results of the latter have improved in recent years, opening up a broad spectrum of new possibilities. We present the case of an asymptomatic 15-day-old neonate who presented an arteriovenous malformation of the vein of Galen and who was treated with endovascular occlusion of the arterial afferents. An excellent result was obtained with no evidence of neurological abnormalities.

Cerebral Veins↗

PubMed2000

Counting nouns and verbs in the input: differential frequencies, different kinds of learning?

Previous research has focused on evaluating the nouns and verbs in parents' input through type/token ratios. This research offers an additional means of evaluating parent speech by first examining the frequencies of individual nouns, verbs and descriptors and second examining the learning task presented to children. Study 1 examines 25 transcripts from the CHILDES database of English-speaking parents' speech to children at five developmental levels ranging from 0;11 to 2;11 in age. Study 2 examines 50 transcripts from the CHILDES database of Mandarin-speaking caregivers' speech to children ranging from 1;9 to 2;3 in age. The results suggest that the patterns of frequency for individual nouns and individual verbs are different, but that the frequency patterns for nouns and the frequency patterns for verbs are similar in English and Mandarin. Further, this research suggests that in both languages the nouns in parents' input are similarly organized: the most frequent nouns spoken to children tend to name solid objects that share a similar shape. In contrast verbs' meanings in both languages tend to include more variable conceptual relations.

Child Language↗

PubMed1985

If it changes it must be a process: study of emotion and coping during three stages of a college examination.

This natural experiment provides substantial evidence for the following major themes, which are based on a cognitively oriented, process-centered theory of stress and coping: First, a stressful encounter should be viewed as a dynamic, unfolding process, not as a static, unitary event. Emotion and coping (including the use of social support) were assessed at three stages of a midterm examination: the anticipation stage before the exam, the waiting stage after the exam and before grades were announced, and after grades were posted. For the group as a whole there were significant changes in emotions and coping (including the use of social support) across the three stages. Second, people experience seemingly contradictory emotions and states of mind during every stage of an encounter. In this study, for example, subjects experienced both threat emotions and challege emotions. The complexity of emotions and their cognitive appraisals reflects ambiguity regarding the multifaceted nature of the exam and its meanings, especially during the anticipation stage. Third, coping is a complex process. On the average, subjects used combinations of most of the available forms of problem-focused coping and emotion-focused coping at every stage of the exam. Different forms of coping were salient during the anticipation and waiting stages. Problem-focused coping and emphasizing the positive were more prominent during the former, and distancing more prominent during the latter. Finally, despite normatively shared emotional reactions at each stage, substantial individual differences remained. Using selected appraisal and coping variables, and taking grade point averages (GPA) into account, approximately 48% of the variances in threat and challenge emotions at the anticipation stage was explained. Controlling for variance due to the grade received, appraisal, and coping variables accounted for 28% of the variance in positive and negative emotions at the outcome stage. Including grade, 57% of the variance in positive emotions at outcome and 61% of the negative emotions at outcome were explained.

Adaptation, Psychological↗