45 results on '"Eves R"'
Search Results
2. Social functioning in adults born very preterm:individual participant meta-analysis
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Ni, Y. (Yanyan), Mendonça, M. (Marina), Baumann, N. (Nicole), Eves, R. (Robert), Kajantie, E. (Eero), Hovi, P. (Petteri), Tikanmäki, M. (Marjaana), Räikkönen, K. (Katri), Heinonen, K. (Kati), Indredavik, M. S. (Marit S.), Evensen, K. I. (Kari-Anne I.), Johnson, S. (Samantha), Marlow, N. (Neil), and Wolke, D. (Dieter)
- Subjects
social adjustment ,very low birth weight ,individual participant data ,infant ,weight measurement scales - Abstract
Context: There is a lack of research on individual perceptions of social experiences and social relationships among very preterm (VP) adults compared with term-born peers. Objective: To investigate self-perceived social functioning in adults born VP (
- Published
- 2021
3. Small for Gestational Age-Cognitive Performance From Infancy to Adulthood: An Observational Study
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Eves, R., primary, Mendonça, M., additional, Bartmann, P., additional, and Wolke, D., additional
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- 2021
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4. Crystal structure of Rhagium Mordax antifreeze protein
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Ye, Q., primary, Eves, R., additional, Campbell, R.L., additional, and Davies, P.L., additional
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- 2020
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5. Small for gestational age—cognitive performance from infancy to adulthood: an observational study
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Eves, R, primary, Mendonça, M, additional, Bartmann, P, additional, and Wolke, D, additional
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- 2020
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6. Origin Of Calcareous Sediments in the Holocene Pigeon Creek Tidal Lagoon and Tidal Delta, San Salvador Island, Bahamas
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Welle, B, primary, Hirsch, A, additional, Davis, L, additional, Johnson, A, additional, Hunt, G, additional, and Eves, R, additional
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- 2004
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7. TUNNEL LINING DESIGN AND PROCUREMENT.
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EVES, R C W, primary and CURTIS, D J, additional
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- 1992
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8. Resisting global AIDS knowledges: born-again christian narratives of the epidemic from papua new Guinea.
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Eves R
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- 2012
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9. TUNNEL LINING DESIGN AND PROCUREMENT.
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CURTIS, D J and EVES, R C W
- Abstract
Tunnel lining design procurement and R. c. W. Eves, BSc(Eng),MICE and D. J. Curtis, BSc(Eng), MSc(Eng), FICE DIG, W In this Paper the design studies and civ.Engng, Channel Tunnel Part I : Tunnels 1992,127-143 Proc. Instn Civ. methods are described for both precast concrete and spheroidal graphite cast iron (SGI) linings, together w i t h an outline of the design requirements of the construction contract...
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- 1992
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10. Gas turbine engine fuel control systems
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Eves, R
- Published
- 1975
11. Romantic and sexual relationships of young adults born very preterm: An individual participant data meta-analysis.
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Mendonça M, Ni Y, Baumann N, Darlow BA, Horwood J, Doyle LW, Cheong JLY, Anderson PJ, Bartmann P, Marlow N, Johnson S, Kajantie E, Hovi P, Nosarti C, Indredavik MS, Evensen KAI, Räikkönen K, Heinonen K, van der Pal S, Woodward LJ, Harris S, Eves R, and Wolke D
- Abstract
Aim: To compare romantic and sexual relationships between adults born very preterm (VP; <32 weeks of gestation) or with very low birth weight (VLBW; <1500 g) and at term, and to evaluate potential biological and environmental explanatory factors among VP/VLBW participants., Methods: This individual participant data (IPD) meta-analysis included longitudinal studies assessing romantic and sexual relationships in adults (mean sample age ≥ 18 years) born VP/VLBW compared with term-born controls. Following PRISMA-IPD guidelines, 11 of the 13 identified cohorts provided IPD from 1606 VP/VLBW adults and 1659 term-born controls. IPD meta-analyses were performed using one-stage approach., Results: Individuals born VP/VLBW were less likely to be in a romantic relationship (OR 0.49; 95% CI 0.31-0.76), to be married/cohabiting (OR 0.70, 95% CI 0.53-0.92), or to have had sexual intercourse (OR 0.21, 95% CI 0.09-0.36) than term-born adults. If sexually active, VP/VLBW participants were more likely to experience their first sexual intercourse after the age of 18 years (OR 1.93, 95% CI 1.24-3.01) than term-born adults. Among VP/VLBW adults, males, and those with neurosensory impairment were least likely to experience romantic relationships., Conclusions: These findings reflect less optimal social functioning and may have implications for socioeconomic and health outcomes of adults born VP/VLBW., (© 2024 The Author(s). Acta Paediatrica published by John Wiley & Sons Ltd on behalf of Foundation Acta Paediatrica.)
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- 2024
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12. Protein inclusion into ice can dissociate subunits.
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Eves R and Davies PL
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- Protein Subunits chemistry, Protein Subunits isolation & purification, Recombinant Fusion Proteins chemistry, Recombinant Fusion Proteins genetics, Recombinant Fusion Proteins isolation & purification, Recombinant Fusion Proteins metabolism, Escherichia coli genetics, Escherichia coli metabolism, Ice, Antifreeze Proteins chemistry, Antifreeze Proteins metabolism, Antifreeze Proteins isolation & purification, Antifreeze Proteins genetics
- Abstract
An antifreeze protein's inclusion into ice can be used to purify it from other proteins and solutes. Domains that are covalently attached to the antifreeze protein are also drawn into the ice such that the ice-binding portion of the fusion protein can be used as an affinity tag. Here we have explored the use of ice-affinity tags on multi-subunit proteins. When an ice-binding protein was attached as a tag to multisubunit complexes a substantial portion of each multimer dissociated during overgrowth by the ice. The protein subunit attached to the affinity tag was enriched in the ice and the other subunit was appreciably excluded. We suggest that step growth of the advancing ice front generates shearing forces on the bound complex that can disrupt non-covalent protein-protein interactions. This will effectively limit the use of ice-affinity tags to single subunit proteins., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2024
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13. Sugar-binding and split domain combinations in repeats-in-toxin adhesins from Vibrio cholerae and Aeromonas veronii mediate cell-surface recognition and hemolytic activities.
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Sherik M, Eves R, Guo S, Lloyd CJ, Klose KE, and Davies PL
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- Animals, Humans, Aeromonas veronii metabolism, Fucose metabolism, Adhesins, Bacterial metabolism, Polysaccharides metabolism, Sugars metabolism, Mammals metabolism, Vibrio cholerae genetics, Vibrio cholerae metabolism, Cholera, Toxins, Biological metabolism
- Abstract
Many pathogenic Gram-negative bacteria use repeats-in-toxin adhesins for colonization and biofilm formation. In the cholera agent Vibrio cholerae , flagellar-regulated hemagglutinin A (FrhA) enables these functions. Using bioinformatic analysis, a sugar-binding domain was identified in FrhA adjacent to a domain of unknown function. AlphaFold2 indicated the boundaries of both domains to be slightly shorter than previously predicted and assisted in the recognition of the unknown domain as a split immunoglobulin-like fold that can assist in projecting the sugar-binding domain toward its target. The AlphaFold2-predicted structure is in excellent agreement with the molecular envelope obtained from small-angle X-ray scattering analysis of a recombinant construct spanning the sugar-binding and unknown domains. This two-domain construct was probed by glycan micro-array screening and showed binding to mammalian fucosylated glycans, some of which are characteristic erythrocyte markers and intestinal cell epitopes. Isothermal titration calorimetry further showed the construct-bound l-fucose with a K
d of 21 µM. Strikingly, this recombinant protein construct bound and lysed erythrocytes in a concentration-dependent manner, and its hemolytic activity was blocked by the addition of l-fucose. A protein ortholog construct from Aeromonas veronii was also produced and showed a similar glycan-binding pattern, binding affinity, erythrocyte-binding, and hemolytic activities. As demonstrated here with Hep-2 cells, fucose-based inhibitors of this sugar-binding domain can potentially be developed to block colonization by V. cholerae and other pathogenic bacteria that share this adhesin domain.IMPORTANCEThe bacterium, Vibrio cholerae , which causes cholera, uses an adhesion protein to stick to human cells and begin the infection process. One part of this adhesin protein binds to a particular sugar, fucose, on the surface of the target cells. This binding can lead to colonization and killing of the cells by the bacteria. Adding l-fucose to the bacteria before they bind to the human cells can prevent attachment and has promise as a preventative drug to protect against cholera., Competing Interests: The authors declare no conflict of interest.- Published
- 2024
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14. Parents' life satisfaction prior to and following preterm birth.
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Eves R, Baumann N, Bilgin A, Schnitzlein D, Richter D, Wolke D, and Lemola S
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- Female, Pregnancy, Infant, Newborn, Humans, Infant, Birth Weight, Prospective Studies, Infant, Very Low Birth Weight, Parents, Personal Satisfaction, Infant, Extremely Premature, Premature Birth
- Abstract
The current study tested whether the reported lower wellbeing of parents after preterm birth, relative to term birth, is a continuation of a pre-existing difference before pregnancy. Parents from Germany (the German Socio-Economic Panel Study, N = 10,649) and the United Kingdom (British Household Panel Study and Understanding Society, N = 11,012) reported their new-born's birthweight and gestational age, subsequently categorised as very preterm or very low birthweight (VP/VLBW, < 32 weeks or < 1500 g), moderately/late preterm or low birthweight (MLP/LBW, ≥ 32 weeks and < 37 weeks/≥ 1500 g and < 2500 g), or term-born (≥ 37 weeks and ≥ 2500 g). Mixed models were used to analyse life satisfaction, an aspect of wellbeing, at four assessments-two years and six months before birth and six months and two years afterwards. Two years before birth, satisfaction of prospective term-born, MLP/LBW, or VP/VLBW mothers did not significantly differ. However, mothers of VP/VLBWs had lower satisfaction relative to mothers of term-borns at both assessments post-birth. Among fathers, satisfaction levels were similarly equivalent two years before birth. Subsequently, fathers of VP/VLBWs temporarily differed in satisfaction six months post-birth relative to fathers of term-borns. Results indicate that parents' lower life satisfaction after VP/VLBW birth is not a continuation of pre-existing life satisfaction differences., (© 2023. The Author(s).)
- Published
- 2023
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15. A peptide-binding domain shared with an Antarctic bacterium facilitates Vibrio cholerae human cell binding and intestinal colonization.
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Lloyd CJ, Guo S, Kinrade B, Zahiri H, Eves R, Ali SK, Yildiz F, Voets IK, Davies PL, and Klose KE
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- Animals, Humans, Infant, Mice, Bacteria, Cell Aggregation, Gastrointestinal Tract, Intestines, Diatoms, Vibrio cholerae genetics
- Abstract
Vibrio cholerae, the causative agent of the disease cholera, is responsible for multiple pandemics. V. cholerae binds to and colonizes the gastrointestinal tract within the human host, as well as various surfaces in the marine environment (e.g., zooplankton) during interepidemic periods. A large adhesin, the Flagellar Regulated Hemagglutinin A (FrhA), enhances binding to erythrocytes and epithelial cells and enhances intestinal colonization. We identified a peptide-binding domain (PBD) within FrhA that mediates hemagglutination, binding to epithelial cells, intestinal colonization, and facilitates biofilm formation. Intriguingly, this domain is also found in the ice-binding protein of the Antarctic bacterium Marinomonas primoryensis , where it mediates binding to diatoms. Peptide inhibitors of the M. primoryensis PBD inhibit V. cholerae binding to human cells as well as to diatoms and inhibit biofilm formation. Moreover, the M. primoryensis PBD inserted into FrhA allows V. cholerae to bind human cells and colonize the intestine and also enhances biofilm formation, demonstrating the interchangeability of the PBD from these bacteria. Importantly, peptide inhibitors of PBD reduce V. cholerae intestinal colonization in infant mice. These studies demonstrate how V. cholerae uses a PBD shared with a diatom-binding Antarctic bacterium to facilitate intestinal colonization in humans and biofilm formation in the environment.
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- 2023
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16. Association of Birth Weight Centiles and Gestational Age With Cognitive Performance at Age 5 Years.
- Author
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Eves R, Wolke D, Spiegler J, and Lemola S
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- Child, Infant, Infant, Newborn, Young Adult, Adolescent, Female, Humans, Male, Child, Preschool, Birth Weight, Cohort Studies, Longitudinal Studies, Australia, Gestational Age, Cognition
- Abstract
Importance: Birth weight percentiles (BWPs) are often dichotomized at the 10th percentile and show statistically significant association with later cognitive performance, for both preterm and term-born children. However, research testing nonlinear associations between BWPs and cognitive performance is scarce., Objective: To investigate culturally invariant, nonlinear associations of BWPs and gestational age with later cognitive performance., Design, Setting, and Participants: In this cohort study, participants with valid neonatal and cognitive data were combined from 4 observational cohorts, including the Millennium Cohort Study, the National Longitudinal Survey of Youth 1979 Child and Young Adult cohort, Growing Up in Ireland, and the Longitudinal Study of Australian Children, with children born between 2000 and 2002, 1980 and 2010, 2007 and 2008, and 2003 and 2004, respectively. Neonatal data were parent reported before age 1 year. At approximately 5 years of age, multiple cognitive tests were performed. Follow-up at 5 years of age was the predominant focus. Data were analyzed July 17, 2023., Exposure: The parent-reported neonatal data were used to calculate BWPs according to the Fenton growth chart., Main Outcome and Measure: Scores for IQ were created from multiple measures of cognition, which were z standardized separately within each cohort., Results: Of 30 643 participants (50.8% male), 7.5% were born preterm (before 37 weeks gestation) and 92.5% were term born (between 37 and 42 weeks gestation). In the pooled data using multivariate adaptive regression splines, IQ linearly increased by 4.2 points as BWPs increased from the first to the 69th percentile before completely plateauing. For gestational age, IQ linearly increased by 1.3 points per week up until 32 weeks, with the association reducing to 0.3 points per week after 32 weeks. The association of BWP with IQ was not moderated by gestational age. For term-born infants, the estimated IQ score was only clinically meaningfully lower than average when birth weight was below the third percentile. Consistent results were found when instead using multivariable regression where gestational age and BWPs were categorized into groups., Conclusions and Relevance: In this cohort study, lower BWPs and gestational age were independently associated with lower IQ. For term-born infants, a cutoff of the third percentile would be more appropriate than the traditionally used 10th percentile when the aim is estimating meaningful cognitive differences.
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- 2023
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17. Lower hypothalamus subunit volumes link with impaired long-term body weight gain after preterm birth.
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Ruzok T, Schmitz-Koep B, Menegaux A, Eves R, Daamen M, Boecker H, Rieger-Fackeldey E, Priller J, Zimmer C, Bartmann P, Wolke D, Sorg C, and Hedderich DM
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- Adult, Female, Humans, Infant, Newborn, Longitudinal Studies, Brain, Hypothalamus, Premature Birth, Body-Weight Trajectory
- Abstract
Introduction: Preterm birth is associated with an increased risk for impaired body weight gain. While it is known that in prematurity several somatic and environmental factors (e.g., endocrine factors, nutrition) modulate short- and long-term body weight gain, the contribution of potentially impaired body weight control in the brain remains elusive. We hypothesized that the structure of hypothalamic nuclei involved in body weight control is altered after preterm birth, with these alterations being associated with aberrant body weight development into adulthood., Materials and Methods: We assessed 101 very preterm (i.e., <32 weeks of gestational age) and/or very low birth weight (i.e., <1500g; VP/VLBW) and 110 full-term born (FT) adults of the population-based Bavarian Longitudinal Study with T1-weighted MRI, deep learning-based hypothalamus subunit segmentation, and multiple body weight assessments from birth into adulthood., Results: Volumes of the whole hypothalamus and hypothalamus subunits relevant for body weight control were reduced in VP/VLBW adults and associated with birth variables (i.e., gestational age and intensity of neonatal treatment), body weight (i.e., weight at birth and adulthood), and body weight trajectories (i.e., trajectory slopes and cluster/types such as long-term catch-up growth). Particularly, VP/VLBW subgroups, whose individuals showed catch-up growth and/or were small for gestational age, were mostly associated with volumes of distinct hypothalamus subunits such as lateral or infundibular/ventromedial hypothalamus., Conclusion: Results demonstrate lower volumes of body weight control-related hypothalamus subunits after preterm birth that link with long-term body weight gain. Data suggest postnatal development of body weight -related hypothalamic nuclei in VP/VLBW individuals that corresponds with distinct body weight trajectories into adulthood., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Ruzok, Schmitz-Koep, Menegaux, Eves, Daamen, Boecker, Rieger-Fackeldey, Priller, Zimmer, Bartmann, Wolke, Sorg and Hedderich.)
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- 2022
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18. Social Functioning in Adults Born Very Preterm: Individual Participant Meta-analysis.
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Ni Y, Mendonça M, Baumann N, Eves R, Kajantie E, Hovi P, Tikanmäki M, Räikkönen K, Heinonen K, Indredavik MS, Evensen KI, Johnson S, Marlow N, and Wolke D
- Subjects
- Adult, Age Factors, Cohort Studies, Education, Employment, Family Relations, Female, Friends, Gestational Age, Humans, Infant, Newborn, Male, Self Report, Sex Factors, Social Class, Spouses, Infant, Extremely Premature psychology, Infant, Very Low Birth Weight psychology, Interpersonal Relations, Social Interaction
- Abstract
Context: There is a lack of research on individual perceptions of social experiences and social relationships among very preterm (VP) adults compared with term-born peers., Objective: To investigate self-perceived social functioning in adults born VP (<32 weeks' gestation) and/or with very low birth weight (VLBW) (<1500g) compared with term-born adults (≥37 weeks' gestation) using an individual participant data (IPD) meta-analysis., Data Sources: Two international consortia: Research on European Children and Adults born Preterm and Adults Born Preterm International Collaboration., Study Selection: Cohorts with outcomes assessed by using the Adult Self-Report Adaptive Functioning scales (friends, spouse/partner, family, job, and education) in both groups., Data Extraction: IPD from 5 eligible cohorts were collected. Raw-sum scores for each scale were standardized as z scores by using mean and SD of controls for each cohort. Pooled effect size was measured by difference (Δ) in means between groups., Results: One-stage analyses (1285 participants) revealed significantly lower scores for relationships with friends in VP/VLBW adults compared with controls (Δ -0.37, 95% confidence interval [CI]: -0.61 to -0.13). Differences were similar after adjusting for sex, age, and socioeconomic status (Δ -0.39, 95% CI: -0.63 to -0.15) and after excluding participants with neurosensory impairment (Δ -0.34, 95% CI: -0.61 to -0.07). No significant differences were found in other domains., Limitations: Generalizability of research findings to VP survivors born in recent decades., Conclusions: VP/VLBW adults scored their relationship with friends lower but perceived their family and partner relationships, as well as work and educational experiences, as comparable to those of controls., Competing Interests: POTENTIAL CONFLICT OF INTEREST: Dr Marlow declares consultancy fees from RSM Consulting, Takeda, and Novartis in the past 3 years outside this study. The other authors have indicated they have no potential conflicts of interest to disclose., (Copyright © 2021 by the American Academy of Pediatrics.)
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- 2021
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19. Association of Very Preterm Birth or Very Low Birth Weight With Intelligence in Adulthood: An Individual Participant Data Meta-analysis.
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Eves R, Mendonça M, Baumann N, Ni Y, Darlow BA, Horwood J, Woodward LJ, Doyle LW, Cheong J, Anderson PJ, Bartmann P, Marlow N, Johnson S, Kajantie E, Hovi P, Nosarti C, Indredavik MS, Evensen KI, Räikkönen K, Heinonen K, Zeitlin J, and Wolke D
- Subjects
- Adult, Bronchopulmonary Dysplasia epidemiology, Cerebral Hemorrhage epidemiology, Educational Status, Gestational Age, Humans, Infant, Newborn, Infant, Extremely Premature, Infant, Very Low Birth Weight, Intelligence
- Abstract
Importance: Birth before 32 weeks' gestation (very preterm [VPT]) and birth weight below 1500 g (very low birth weight [VLBW]) have been associated with lower cognitive performance in childhood. However, there are few investigations of the association of neonatal morbidities and maternal educational levels with the adult cognitive performance of individuals born VPT or VLBW (VPT/VLBW)., Objective: To assess differences in adult IQ between VPT/VLBW and term-born individuals and to examine the association of adult IQ with cohort factors, neonatal morbidities, and maternal educational level among VPT/VLBW participants., Data Sources: Systematic review of published data from PubMed and meta-analysis of individual participant data (IPD) of cohorts from 2 consortia (Research on European Children and Adults Born Preterm [RECAP] and Adults Born Preterm International Collaboration [APIC])., Study Selection: The meta-analysis included prospective longitudinal cohort studies that assessed the full-scale IQ of adults born VPT or VLBW and respective control groups comprising term-born adults., Data Extraction and Synthesis: The study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline for analyses of individual participant data and identified 8 studies that provided data from 2135 adults (1068 VPT/VLBW and 1067 term-born participants) born between 1978 and 1995. Meta-analyses of IPD were performed using a 1-stage approach, treating VPT birth or VLBW and cohort as random effects., Main Outcomes and Measures: Full-scale IQ scores were converted to z scores within each cohort using the combined SD of VPT/VLBW participants and a control group of term-born participants, with scores centered on the mean of the control group., Results: A total of 426 records were identified and screened. After exclusions, 13 studies were included in the aggregate meta-analysis. The IPD meta-analysis included 8 of the 9 RECAP and APIC cohorts with adult IQ data. The mean (SD) age among the 8 IPD cohorts was 24.6 (4.3) years, and 1163 participants (54.5%) were women. In unadjusted analyses, VPT/VLBW participants had mean adult IQ scores that were 0.78 SD (95% CI, -0.90 to -0.66 SD) lower than term-born participants, equivalent to a difference of 12 IQ points. Among VPT/VLBW participants, lower gestational age (score difference per week of gestation, 0.11; 95% CI, 0.07-0.14), lower birth weight z scores (score difference per 1.0 SD, 0.21; 95% CI, 0.14-0.28), the presence of neonatal bronchopulmonary dysplasia (score difference, -0.16; 95% CI, -0.30 to -0.02) or any grade of intraventricular hemorrhage (score difference, -0.19; 95% CI, -0.33 to -0.05), and lower maternal educational level (score difference, 0.26; 95% CI, 0.17-0.35) were all significantly associated with lower IQ scores in adulthood., Conclusions and Relevance: In this IPD meta-analysis, lower gestational age, lower weight for gestational age, neonatal morbidities, and lower maternal educational levels were all important risk factors associated with lower IQ among young adults born VPT or VLBW.
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- 2021
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20. Marital sexual violence and conjugality in highlands Papua New Guinea.
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Eves R
- Subjects
- Female, Humans, Male, Papua New Guinea, Sexual Behavior, Violence, Marriage, Sex Offenses
- Abstract
Many male coffee farmers in the highlands of Papua New Guinea believe they have a right to sex with their spouse without regard to her wishes. Drawing on quantitative and qualitative data, I argue that such sexual violence is best framed within local understandings of what marriage involves - an implicit contract which conveys rights and responsibilities to each partner in a marriage. Changes brought by modernity are transforming traditional understandings of conjugality, causing some discrepancies in partners' understanding of what they have agreed to. Too many women continue to endure marital rape, but some signs of improvement are discernible.
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- 2021
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21. Structural Basis of Ligand Selectivity by a Bacterial Adhesin Lectin Involved in Multispecies Biofilm Formation.
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Guo S, Vance TDR, Zahiri H, Eves R, Stevens C, Hehemann JH, Vidal-Melgosa S, and Davies PL
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- Binding Sites, Crystallography, X-Ray, Ligands, Marinomonas chemistry, Models, Molecular, Protein Conformation, Adhesins, Bacterial chemistry, Adhesins, Bacterial metabolism, Biofilms growth & development, Lectins chemistry, Lectins metabolism, Marinomonas metabolism
- Abstract
Carbohydrate recognition by lectins governs critical host-microbe interactions. Mp PA14 ( Marinomonas primoryensis PA14 domain) lectin is a domain of a 1.5-MDa adhesin responsible for a symbiotic bacterium-diatom interaction in Antarctica. Here, we show that Mp PA14 binds various monosaccharides, with l-fucose and N -acetylglucosamine being the strongest ligands (dissociation constant [ K
d ], ∼150 μM). High-resolution structures of Mp PA14 with 15 different sugars bound elucidated the molecular basis for the lectin's apparent binding promiscuity but underlying selectivity. Mp PA14 mediates strong Ca2+ -dependent interactions with the 3,4-diols of l-fucopyranose and glucopyranoses, and it binds other sugars via their specific minor isomers. Thus, Mp PA14 only binds polysaccharides like branched glucans and fucoidans with these free end groups. Consistent with our findings, adhesion of Mp PA14 to diatom cells was selectively blocked by l-fucose, but not by N -acetyl galactosamine. The Mp PA14 lectin homolog present in a Vibrio cholerae adhesin was produced and was shown to have the same sugar binding preferences as Mp PA14. The pathogen's lectin was unable to effectively bind the diatom in the presence of fucose, thus demonstrating the antiadhesion strategy of blocking infection via ligand-based antagonists. IMPORTANCE Bacterial adhesins are key virulence factors that are essential for the pathogen-host interaction and biofilm formation that cause most infections. Many of the adhesin-driven cell-cell interactions are mediated by lectins. Our study reveals for the first time the molecular basis underlying the binding selectivity of a common bacterial adhesin lectin from the marine bacterium Marinomonas primoryensis , homologs of which are found in both environmental and pathogenic species. The lectin-ligand interactions illustrated at the atomic level guided the identification of a ligand that serves as an inhibitor to block bacterium-host adhesion. With conventional bactericidal antibiotics losing their potency due to resistance, our work gives critical insight into an antiadhesion strategy to treat bacterial infections., (Copyright © 2021 Guo et al.)- Published
- 2021
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22. Ice recrystallization inhibition activity varies with ice-binding protein type and does not correlate with thermal hysteresis.
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Gruneberg AK, Graham LA, Eves R, Agrawal P, Oleschuk RD, and Davies PL
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- Animals, Antifreeze Proteins metabolism, Cryopreservation methods, Crystallization, Fishes, Freezing, Insecta, Carrier Proteins, Ice
- Abstract
Ice-binding proteins (IBPs) inhibit the growth of ice through surface adsorption. In some freeze-resistant fishes and insects, circulating IBPs serve as antifreeze proteins to stop ice growth by lowering the freezing point. Plants are less able to avoid freezing and some use IBPs to minimize the damage caused in the frozen state by ice recrystallization, which is the growth of large ice grains at the expense of small ones. Here we have accurately and reproducibly measured the ice recrystallization inhibition (IRI) activity of over a dozen naturally occurring IBPs from fishes, insects, plants, and microorganisms using a modified 'splat' method on serial dilutions of IBPs whose concentrations were determined by amino acid analysis. The endpoint of IRI, which was scored as the lowest protein concentration at which no recrystallization was observed, varied for the different IBPs over two orders of magnitude from 1000 nM to 5 nM. Moreover, there was no apparent correlation between their IRI levels and reported antifreeze activities. IBPs from insects and fishes had similar IRI activity, even though the insect IBPs are typically 10x more active in freezing point depression. Plant IBPs had weak antifreeze activity but were more effective at IRI. Bacterial IBPs involved in ice adhesion showed both strong freezing point depression and IRI. Two trends did emerge, including that basal plane binding IBPs correlated with stronger IRI activity and larger IBPs had higher IRI activity., (Copyright © 2021 Elsevier Inc. All rights reserved.)
- Published
- 2021
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23. Small for gestational age-cognitive performance from infancy to adulthood: an observational study.
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Eves R, Mendonça M, Bartmann P, and Wolke D
- Subjects
- Adolescent, Adult, Child, Child, Preschool, Humans, Infant, Infant, Newborn, Infant, Premature, Infant, Very Low Birth Weight, Longitudinal Studies, Young Adult, Cognition, Infant, Small for Gestational Age psychology
- Abstract
Objective: To determine whether cognitive performance from infancy to adulthood is affected by being born small for gestational age (SGA), and if this depends on the SGA reference used. Furthermore, to determine SGA's effect while considering the effects of very preterm/very low birthweight (VP/VLBW), socio-economic status (SES) and parent-infant relationship., Design, Setting and Population: A total of 414 participants (197 term-born, 217 VP/VLBW) of the Bavarian Longitudinal Study., Methods: Small for gestational age was classified using neonatal or fetal growth references. SES and the parent-infant relationship were assessed before the infant was 5 months old., Main Outcome Measures: Developmental (DQ) and intelligence (IQ) tests assessed cognitive performance on six occasions, from 5 months to 26 years of age., Results: The fetal reference classified more infants as SGA (<10th centile) than the neonatal reference (n = 138, 33% versus n = 75, 18%). Using linear mixed models, SGA was associated with IQ -8 points lower than appropriate for gestational age, regardless of reference used (95% CI -13.66 to -0.64 and 95% CI -13.75 to -1.98). This difference narrowed minimally into adulthood. Being VP/VLBW was associated with IQ -16 (95% CI -21.01 to -10.04) points lower than term-born participants. Low SES was associated with IQ -14 (95% CI -18.55 to -9.06) points lower than high SES. A poor parent-infant relationship was associated with IQ -10 points lower than those with a good relationship (95% CI -13.91 to -6.47)., Conclusions: Small for gestational age is associated with lower IQ throughout development, independent of VP/VLBW birth, low SES or poor parent-child relationship. Social factors effects on IQ comparable to those of SGA and should be considered for interventions., Tweetable Abstract: Small for gestational age is associated with lower cognitive performance from infancy to adulthood., (© 2020 The Authors. BJOG: An International Journal of Obstetrics and Gynaecology published by John Wiley & Sons Ltd on behalf of Royal College of Obstetricians and Gynaecologists.)
- Published
- 2020
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24. Medical pluralism, Pentecostal healing and contests over healing power in Papua New Guinea.
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Eves R and Kelly-Hanku A
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- Anthropology, Cultural, Christianity, Humans, Papua New Guinea, Cultural Diversity, Protestantism
- Abstract
This paper is based on long-term ethnographic fieldwork among the Lelet of New Ireland Province, Papua New Guinea. It draws on qualitative interviews with Pentecostal Christians intended to examine their understanding of Christianity and how this relates to their cultural practices - in this case, how their Pentecostalism affects their therapeutic beliefs and practices. The frequent observation that therapeutic repertoires are becoming less discrete is substantiated by the Lelet case, for in their search for therapy, the Lelet often cross the borders of different repertoires, seeing no contradiction, for example, between combining a vernacular therapy with biomedicine. With the advent of Pentecostalism, the issue has become far more complex. The Lelet therapeutic culture remains pluralist, but the research shows that Lelet Pentecostals are increasingly viewing their own Christian-based forms of healing as in competition with other therapies, especially vernacular therapies. This competitive outlook has brought a demonization of vernacular therapies, which are labelled 'satanic' and their use discouraged. In fact, Pentecostalism is refashioning the realm of therapy: rather than border crossing and mixing of therapeutic repertoires, the situation is increasingly dominated by notions of mutual exclusivity. In order to comprehend the full complexity of medical pluralism, it is now necessary not only to examine how the borders of the different therapeutic repertoires are blurred, destabilized or reconfigured but also how they may be demarcated and policed. In other words, we argue that medical pluralism is being eroded by its interaction with Pentecostalism., (Copyright © 2020 Elsevier Ltd. All rights reserved.)
- Published
- 2020
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25. Crystal structure of an insect antifreeze protein reveals ordered waters on the ice-binding surface.
- Author
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Ye Q, Eves R, Campbell RL, and Davies PL
- Subjects
- Animals, Crystallography, X-Ray, Antifreeze Proteins chemistry, Coleoptera chemistry, Ice, Insect Proteins chemistry
- Abstract
Antifreeze proteins (AFPs) are characterized by their ability to adsorb to the surface of ice crystals and prevent any further crystal growth. AFPs have independently evolved for this purpose in a variety of organisms that encounter the threat of freezing, including many species of polar fish, insects, plants and microorganisms. Despite their diverse origins and structures, it has been suggested that all AFPs can organize ice-like water patterns on one side of the protein (the ice-binding site) that helps bind the AFP to ice. Here, to test this hypothesis, we have solved the crystal structure at 2.05 Å resolution of an AFP from the longhorn beetle, Rhagium mordax with five molecules in the unit cell. This AFP is hyperactive, and its crystal structure resembles that of the R. inquisitor ortholog in having a β-solenoid fold with a wide, flat ice-binding surface formed by four parallel rows of mainly Thr residues. The key difference between these structures is that the R. inquisitor AFP crystallized with its ice-binding site (IBS) making protein-protein contacts that limited the surface water patterns. Whereas the R. mordax AFP crystallized with the IBSs exposed to solvent enabling two layers of unrestricted ordered surface waters to be seen. These crystal waters make close matches to ice lattice waters on the basal and primary prism planes., (© 2020 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.)
- Published
- 2020
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26. The Role of Executive and General Cognitive Functioning in the Attention Problems of Very and Extremely Preterm Adults.
- Author
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Eves R, von Mühlenen A, Mendonça M, Johnson S, O'Reilly H, Bartmann P, Marlow N, and Wolke D
- Subjects
- Adult, Attention Deficit Disorder with Hyperactivity epidemiology, Child, Cognitive Dysfunction epidemiology, Female, Germany epidemiology, Humans, Infant, Extremely Premature physiology, Infant, Newborn, Inhibition, Psychological, Longitudinal Studies, Male, Memory, Short-Term physiology, Attention Deficit Disorder with Hyperactivity physiopathology, Cognitive Dysfunction physiopathology, Executive Function physiology, Infant, Low Birth Weight physiology, Infant, Premature physiology, Intelligence physiology
- Abstract
Objective: To determine whether the attention problems in adults born very preterm/very low birth weight (VP/VLBW; <32 weeks' gestation/<1500 g) or extremely preterm (EP; <26 weeks' gestation) are associated with specific executive or general cognitive deficits., Method: Cohorts of VP/VLBW (the Bavarian Longitudinal Study [BLS]) and EP (the EPICure Study) participants were followed from birth to early adulthood, each also following a respective control group. Adult attention deficit hyperactivity disorder (ADHD) symptoms were assessed via self-report in both cohorts and additionally by parent report in the BLS. Participants in both cohorts also had their attention span rated by trained observers. Performed separately in each cohort, hierarchical regression analyses were used to assess whether the association between preterm birth status and attention problems remained after accounting for executive functioning (inhibitory control and working memory) in adulthood, childhood intelligence score (IQ), or sex., Results: In the discovery cohort of the BLS, significant differences were found between VP/VLBW adults and controls for parent-rated inattention (p < 0.001). However, for self-reported measures of ADHD, no significant differences were found in the BLS or in the EPICure replication cohort. In both cohorts, observer-rated attention spans were lower for VP/VLBW and EP participants in comparison to their respective control groups (p < 0.001). In final models for the BLS, inhibitory control and childhood IQ were significantly associated with parent-rated inattention symptoms (p < 0.006), whereas working memory and childhood IQ were significantly associated with observer-rated attention span (p < 0.001). The effect of childhood IQ on observer-rated attention span was replicated in EPICure., Conclusion: VP/VLBW and EP adults are at increased risk of observer-rated attention problems. These problems were predominantly associated with poorer general cognitive ability in early childhood and somewhat with adult executive functioning.
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- 2020
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27. Carrot 'antifreeze' protein has an irregular ice-binding site that confers weak freezing point depression but strong inhibition of ice recrystallization.
- Author
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Wang Y, Graham LA, Han Z, Eves R, Gruneberg AK, Campbell RL, Zhang H, and Davies PL
- Subjects
- Binding Sites, Crystallization, Freezing, Hydrophobic and Hydrophilic Interactions, Protein Conformation, Protein Domains, Antifreeze Proteins chemistry, Antifreeze Proteins metabolism, Daucus carota metabolism, Ice, Plant Proteins chemistry, Plant Proteins metabolism
- Abstract
Ice-binding proteins (IBPs) are found in many biological kingdoms where they protect organisms from freezing damage as antifreeze agents or inhibitors of ice recrystallization. Here, the crystal structure of recombinant IBP from carrot (Daucus carota) has been solved to a resolution of 2.3 Å. As predicted, the protein is a structural homologue of a plant polygalacturonase-inhibiting protein forming a curved solenoid structure with a leucine-rich repeat motif. Unexpectedly, close examination of its surface did not reveal any large regions of flat, regularly spaced hydrophobic residues that characterize the ice-binding sites (IBSs) of potent antifreeze proteins from freeze-resistant fish and insects. An IBS was defined by site-directed mutagenesis of residues on the convex surface of the carrot solenoid. This imperfect site is reminiscent of the irregular IBS of grass 'antifreeze' protein. Like the grass protein, the carrot IBP has weak freezing point depression activity but is extremely active at nanomolar concentrations in inhibiting ice recrystallization. Ice crystals formed in the presence of both plant proteins grow slowly and evenly in all directions. We suggest that this slow, controlled ice growth is desirable for freeze tolerance. The fact that two plant IBPs have evolved very different protein structures to affect ice in a similar manner suggests this pattern of weak freezing point depression and strong ice recrystallization inhibition helps their host to tolerate freezing rather than to resist it., (© 2020 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.)
- Published
- 2020
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28. Synergy between Antifreeze Proteins Is Driven by Complementary Ice-Binding.
- Author
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Berger T, Meister K, DeVries AL, Eves R, Davies PL, and Drori R
- Subjects
- Animals, Crystallization, Fishes metabolism, Models, Molecular, Plants chemistry, Protein Binding, Protein Isoforms chemistry, Recombinant Proteins chemistry, Antifreeze Proteins chemistry, Fish Proteins chemistry, Ice analysis, Plant Proteins chemistry
- Abstract
In some cold-adapted organisms, over a dozen isoforms of antifreeze (glyco)proteins or AF(G)Ps are present. Although these isoforms are structurally similar, their ability to inhibit ice growth varies significantly, and, in some fish, passive isoforms can be much more abundant than the active ones. Laboratory experiments demonstrated more than a decade ago that mixtures of AFP isoforms can exhibit synergistic enhancement of each other's activity. The mechanism of this synergy effect has remained obscure and is addressed here. Using cold-stages, microfluidics, and fluorescence microscopy, the activity of binary mixtures of structurally distinct AF(G)Ps from different fish and plant species was measured. While several mixtures exhibited enhancement, some mixtures exhibited antagonism. These latter mixtures included AF(G)Ps that bind to the same crystal planes, thereby exhibiting competition. Fluorescence microscopy experiments with a synergistic mixture of two isoform types labeled with different dyes showed they bound to different crystal planes. These results helped develop a kinetic description of the mechanism by which AF(G)Ps achieve synergy. The requirements of an active isoform include high adsorption rates, and prism plane binding, while passive isoforms usually bind to a pyramidal plane at slower rates. For synergy to occur, an active isoform first binds to the faster growing prism plane. This binding slows the advancement of the prism plane and creates more pyramidal surfaces to which a passive isoform bind. These results, in part, explain the biological observation of isoform distribution in fish, and the physical chemistry of the synergistic crystal growth inhibition by two inhibitors.
- Published
- 2019
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29. 'Full price, full body': norms, brideprice and intimate partner violence in highlands Papua New Guinea.
- Author
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Eves R
- Subjects
- Adult, Female, Humans, Male, Middle Aged, Papua New Guinea, Qualitative Research, Culture, Intimate Partner Violence, Marriage, Social Norms
- Abstract
This paper draws on qualitative research in Jiwaka Province, in the highlands of Papua New Guinea (PNG), to examine the changing nature of marriage in that context. In particular, it examines how changes in the practice of brideprice have been associated with an increase in intimate partner violence. Violence, a relational process, is to be understood in the context of the customary unequal power relations between men and women. It is argued that men in the highlands of PNG see any gain in power for women as a loss for themselves, and so actively resist it. Men who see their power over women challenged resort to the discourse of brideprice, arguing that the payment of brideprice gives them absolute authority over wives. A good understanding of the norms that sanction violence is a vital step in developing interventions to prevent violence.
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- 2019
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30. Association of physical activity and cardiorespiratory function or BMI and body composition in preterm-born individuals: a systematic review.
- Author
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Spiegler J, Eves R, Mendonça M, and Wolke D
- Subjects
- Forced Expiratory Volume, Humans, Infant, Newborn, Body Composition, Body Mass Index, Exercise, Infant, Premature physiology, Oxygen Consumption
- Abstract
Aim: To evaluate the association of physical activity (PA) and forced expiratory volume in one second (FEV1), peak oxygen consumption (pVO2), body mass index (BMI) and body composition in preterm-born individuals., Methods: Cochrane Library, EMBASE, MEDLINE, AMED, ERIC, Web of Science and PsycInfo were searched with no restriction on language and date of publication from inception to January 2018. Data were extracted comparing preterm-born individuals with different frequencies of PA and the outcome of interest., Results: One randomized controlled, two longitudinal and thirteen cross-sectional studies comprising 1922 preterm-born individuals aged 5-25 were included. Assessment varied from a PA program to accelerometer data, interviews and self-report questionnaires. In preterm-born children, more PA was associated with better cardiorespiratory function in those groups with impaired lung function or with lower BMI in those groups with increased risk factors, but no association was found in unimpaired children. In preterm-born adults, more PA was associated with higher pVO2 and lower BMI., Conclusion: Only tentative conclusions can be drawn, especially regarding differences of the association of PA between preterm- and term-born populations. Further studies are needed to analyse the association of PA in preterm-born individuals with reduced cardiorespiratory function., (©2019 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.)
- Published
- 2019
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31. Laboratory-Scale Isolation of Insect Antifreeze Protein for Cryobiology.
- Author
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Tomalty HE, Graham LA, Eves R, Gruneberg AK, and Davies PL
- Subjects
- Amino Acid Sequence, Animals, Antifreeze Proteins chemistry, Antifreeze Proteins toxicity, Cell Survival drug effects, HEK293 Cells, Humans, Ice, Larva, Monophenol Monooxygenase antagonists & inhibitors, Monophenol Monooxygenase metabolism, Protein Isoforms chemistry, Toxicity Tests, Antifreeze Proteins isolation & purification, Cryobiology, Tenebrio chemistry
- Abstract
Micromolar concentrations of hyperactive antifreeze proteins (AFPs) from insects can prevent aqueous solutions from freezing down to at least -6 °C. To explore cryopreservation of cells, tissues and organs at these temperatures without ice formation, we have developed a protocol to reliably produce ultrapure Tenebrio molitor AFP from cold-acclimated beetle larvae reared in the laboratory. The AFP was prepared from crude larval homogenates through five cycles of rotary ice-affinity purification, which can be completed in one day. Recovery of the AFP at each step was >90% and no impurities were detected in the final product. The AFP is a mixture of isoforms that are more active in combination than any one single component. Toxicity testing of the purified AFP in cell culture showed no inhibition of cell growth. The production process can easily be scaled up to industrial levels, and the AFP used in cryobiology applications was recovered for reuse in good yield and with full activity.
- Published
- 2019
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32. Comparison of diets for Largemouth and Smallmouth Bass in Eastern Lake Ontario using DNA barcoding and stable isotope analysis.
- Author
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Nelson EJH, Holden J, Eves R, and Tufts B
- Subjects
- Animals, DNA analysis, DNA Barcoding, Taxonomic methods, Diet veterinary, Food Analysis methods, Isotope Labeling methods, Perciformes physiology
- Abstract
Largemouth (LMB: Micropterus salmoides) and Smallmouth Bass (SMB: Micropterus dolomieu) are important species in the recreational fisheries of the Laurentian Great Lakes. The invasion of the Round Goby (Neogobius melanostomus) into these lakes has changed several facets of black bass biology, but there is still much to learn about the relationship between these species. Previous dietary analyses have shown Round Goby to be important prey for bass, but have been limited by low visual identification rates of dissected stomach items. Within the present study, DNA barcoding and stable isotope analysis improve prey identification and provide a more quantitative dietary analysis of adult black bass in Lake Ontario, comparing the importance of Round Goby as prey between these two species. Eighty-four LMB (406mm fork length ±4mm SEM) and two hundred sixty-four SMB (422mm ±2mm) obtained as tournament mortalities had prey identified using DNA-based methods. Round Goby was the most prevalent prey species for both predators. The diet of LMB was three times more diverse than that of SMB, which almost entirely consists of Round Goby. Our results provide further support that recent increases in the size of Lake Ontario bass are a result of Round Goby consumption, and that the effects of this dietary shift on body condition are greater for SMB. Techniques developed in this study include reverse-oriented dual priming oligonucleotides used as blocking primers for predator DNA, and an automated design approach of restriction fragment length polymorphism tests for identifying prey DNA barcodes.
- Published
- 2017
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33. Effects of p53-knockout in vascular smooth muscle cells on atherosclerosis in mice.
- Author
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Cao RY, Eves R, Jia L, Funk CD, Jia Z, and Mak AS
- Subjects
- Animals, Aorta metabolism, Apolipoproteins E genetics, Apolipoproteins E metabolism, Atherosclerosis genetics, Cell Movement genetics, Cell Movement physiology, Cells, Cultured, Disease Models, Animal, Mice, Mice, Inbred C57BL, Mice, Knockout, Microscopy, Fluorescence, Plaque, Atherosclerotic genetics, Tumor Suppressor Protein p53 genetics, Atherosclerosis metabolism, Muscle, Smooth, Vascular cytology, Myocytes, Smooth Muscle metabolism, Plaque, Atherosclerotic metabolism, Tumor Suppressor Protein p53 metabolism
- Abstract
In vitro and in vivo evidence has indicated that the tumor suppressor, p53, may play a significant role in the regulation of atherosclerotic plaque formation. In vivo studies using global knockout mice models, however, have generated inconclusive results that do not address the roles of p53 in various cell types involved in atherosclerosis. In this study, we have specifically ablated p53 in vascular smooth muscle cells (VSMC) in the ApoE-/- mouse model to investigate the roles of p53 in VSMC in atherosclerotic plaque formation and stability. We found that p53 deficiency in VSMC alone did not affect the overall size of atherosclerotic lesions. However, there was a significant increase in the number of p53-/- VSMC in the fibrous caps of atherosclerotic plaques in the early stages of plaque development. Loss of p53 results in migration of VSMC at a faster rate using wound healing assays and augments PDGF-induced formation of circular dorsal ruffles (CDR), known to be involved in cell migration and internalization of surface receptors. Furthermore, aortic VSMC from ApoE-/- /p53-/- mice produce significantly more podosomes and are more invasive. We conclude that p53-/- VSMC are enriched in the fibrous caps of lesions at early stages of plaque formation, which is caused in part by an increase in VSMC migration and invasion as shown by p53-/- VSMC in culture having significantly higher rates of migration and producing more CDRs and invasive podosomes.
- Published
- 2017
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34. The roles of akt isoforms in the regulation of podosome formation in fibroblasts and extracellular matrix invasion.
- Author
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Eves R, Oldham R, Jia L, and Mak AS
- Abstract
Mesenchymal cells employ actin-based membrane protrusions called podosomes and invadopodia for cross-tissue migration during normal human development such as embryogenesis and angiogenesis, and in diseases such as atherosclerosis plaque formation and cancer cell metastasis. The Akt isoforms, downstream effectors of phosphatidylinositol 3 kinase (PI3K), play crucial roles in cell migration and invasion, but their involvement in podosome formation and cell invasion is not known. In this study, we have used Akt1 and/or Akt2 knockout mouse embryonic fibroblasts and Akt3-targeted shRNA to determine the roles of the three Akt isoforms in Src and phorbol ester-induced podosome formation, and extracellular matrix (ECM) digestion. We found that deletion or knockdown of Akt1 significantly reduces Src-induced formation of podosomes and rosettes, and ECM digestion, while suppression of Akt2 has little effect. In contrast, Akt3 knockdown by shRNA increases Src-induced podosome/rosette formation and ECM invasion. These data suggest that Akt1 promotes, while Akt3 suppresses, podosome formation induced by Src, and Akt2 appears to play an insignificant role. Interestingly, both Akt1 and Akt3 suppress, while Akt2 enhances, phorbol ester-induced podosome formation. These data show that Akt1, Akt2 and Akt3 play different roles in podosome formation and ECM invasion induced by Src or phorbol ester, thus underscoring the importance of cell context in the roles of Akt isoforms in cell invasion.
- Published
- 2015
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35. Both lipid- and protein-phosphatase activities of PTEN contribute to the p53-PTEN anti-invasion pathway.
- Author
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Poon JS, Eves R, and Mak AS
- Subjects
- Animals, Cell Movement, Muscle, Smooth, Vascular cytology, Muscle, Smooth, Vascular metabolism, Neoplasms metabolism, PTEN Phosphohydrolase genetics, PTEN Phosphohydrolase physiology, Phosphatidylinositol 3-Kinases metabolism, Proto-Oncogene Proteins c-akt metabolism, RNA Interference, RNA, Small Interfering, Rats, STAT3 Transcription Factor metabolism, Signal Transduction, Up-Regulation, src-Family Kinases metabolism, PTEN Phosphohydrolase metabolism, Tumor Suppressor Protein p53 metabolism
- Abstract
We have recently identified mutually antagonizing signaling pathways that regulate podosome formation and invasive phenotypes in Src-transformed vascular smooth muscle cells and fibroblasts. Cross-talks between the anti-invasion p53-PTEN, and the pro-invasion Src-Stat3 and Src-PI3K-Akt pathways serve as a check and balance that dictates the outcome of either an invasive or non-invasive phenotype. Using a retrovirus vector encoding PTEN phosphatase mutants that retain either protein- or lipid-phosphatase activity on a Src(Y527F)background, we report here that both lipid- and protein-phosphatase activities of PTEN contribute to the suppression of Src-induced podosome formation and associated invasive phenotypes in rat aortic smooth muscle cells. This data suggests that p53 up-regulation of PTEN inhibits cell invasion via a two-prong mechanism: inactivating podosome agonists by its protein-phosphatase activity on the one hand, and antagonising the PI3K-Akt pathway by its lipid-phosphatase activity on the other.
- Published
- 2010
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36. Doubles game: Src-Stat3 versus p53-PTEN in cellular migration and invasion.
- Author
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Mukhopadhyay UK, Mooney P, Jia L, Eves R, Raptis L, and Mak AS
- Subjects
- 3T3 Cells, Animals, Base Sequence, Calmodulin-Binding Proteins antagonists & inhibitors, Calmodulin-Binding Proteins genetics, Calmodulin-Binding Proteins physiology, Cell Line, Cell Movement genetics, DNA Primers genetics, Gene Knockdown Techniques, Matrix Metalloproteinase 1 genetics, Matrix Metalloproteinase 1 physiology, Matrix Metalloproteinase 10 genetics, Matrix Metalloproteinase 10 physiology, Matrix Metalloproteinase Inhibitors, Mice, Models, Biological, Mutant Proteins genetics, Mutant Proteins physiology, Myocytes, Smooth Muscle physiology, Neoplasm Invasiveness genetics, Neoplasm Invasiveness physiopathology, PTEN Phosphohydrolase genetics, Phenotype, RNA, Small Interfering genetics, Rats, Recombinant Proteins genetics, Recombinant Proteins metabolism, STAT3 Transcription Factor antagonists & inhibitors, STAT3 Transcription Factor genetics, Signal Transduction, Tumor Suppressor Protein p53 genetics, src-Family Kinases genetics, Cell Movement physiology, PTEN Phosphohydrolase physiology, STAT3 Transcription Factor physiology, Tumor Suppressor Protein p53 physiology, src-Family Kinases physiology
- Abstract
We have recently shown that Src induces the formation of podosomes and cell invasion by suppressing endogenous p53, while enhanced p53 strongly represses the Src-induced invasive phenotype. However, the mechanism by which Src and p53 play antagonistic roles in cell invasion is unknown. Here we show that the Stat3 oncogene is a required downstream effector of Src in inducing podosome structures and related invasive phenotypes. Stat3 promotes Src phenotypes through the suppression of p53 and the p53-inducible protein caldesmon, a known podosome antagonist. In contrast, enhanced p53 attenuates Stat3 function and Src-induced podosome formation by upregulating the tumor suppressor PTEN. PTEN, through the inactivation of Src/Stat3 function, also stabilizes the podosome-antagonizing p53/caldesmon axis, thereby further enhancing the anti-invasive potential of the cell. Furthermore, the protein phosphatase activity of PTEN plays a major role in the negative regulation of the Src/Stat3 pathway and represses podosome formation. Our data suggest that cellular invasiveness is dependent on the balance between two opposing forces: the proinvasive oncogenes Src-Stat3 and the anti-invasive tumor suppressors p53-PTEN.
- Published
- 2010
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37. p53 suppresses Src-induced podosome and rosette formation and cellular invasiveness through the upregulation of caldesmon.
- Author
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Mukhopadhyay UK, Eves R, Jia L, Mooney P, and Mak AS
- Subjects
- Animals, Blood Vessels cytology, Collagen metabolism, Drug Combinations, Enzyme Activation drug effects, Extracellular Matrix drug effects, Extracellular Matrix metabolism, Laminin metabolism, Mice, Microfilament Proteins metabolism, Models, Biological, Myocytes, Smooth Muscle cytology, Myocytes, Smooth Muscle drug effects, Myocytes, Smooth Muscle enzymology, NIH 3T3 Cells, Proteoglycans metabolism, Pseudopodia drug effects, Rats, Tetradecanoylphorbol Acetate pharmacology, Up-Regulation drug effects, Calmodulin-Binding Proteins genetics, Cell Movement drug effects, Proto-Oncogene Proteins pp60(c-src) metabolism, Pseudopodia enzymology, Tumor Suppressor Protein p53 metabolism, Up-Regulation genetics
- Abstract
The tumor-suppressive role of p53 at the level of tumor initiation is well documented. It has also been shown previously that p53 acts against tumor progression/metastasis. However, its role in modulating cell migration and invasion leading to metastasis is poorly understood. In this study, using vascular smooth muscle cells and NIH 3T3 fibroblast cells, we have shown that p53 potently suppresses Src-induced podosome/rosette formation, extracellular matrix digestion, cell migration, and invasion. The overexpression of exogenous wild-type p53 or the activation of the endogenous p53 function suppresses, while the short hairpin RNA-mediated knockdown of p53 expression or the pageing of its function exacerbates, Src-induced migratory and invasive phenotypes. We have also found that p53 expression and function are downregulated in cells stably transformed with constitutively active Src that exhibit aggressive invasive properties. Lastly, p53 upregulates the expression of caldesmon, an actin-binding protein that has been shown to be an inhibitor of podosome/invadopodium formation. The ability of p53 to suppress Src phenotypes in transformed cells was largely abolished by knocking down caldesmon. This study reports a novel molecular mechanism (caldesmon), as well as a structural basis (podosomes/rosettes), to show how p53 can act as an anti-motility/invasion/metastasis agent.
- Published
- 2009
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38. Phorbol ester-induced podosomes in normal human bronchial epithelial cells.
- Author
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Xiao H, Eves R, Yeh C, Kan W, Xu F, Mak AS, and Liu M
- Subjects
- Cell Line, Cell Membrane Structures enzymology, Cell Movement drug effects, Cytoskeleton drug effects, Cytoskeleton metabolism, Epithelial Cells enzymology, Extracellular Matrix drug effects, Extracellular Matrix metabolism, Humans, Matrix Metalloproteinases metabolism, Protein-Tyrosine Kinases metabolism, Pseudopodia drug effects, Pseudopodia metabolism, Vinculin metabolism, Bronchi cytology, Cell Membrane Structures drug effects, Cell Membrane Structures metabolism, Epithelial Cells cytology, Epithelial Cells drug effects, Phorbol 12,13-Dibutyrate pharmacology
- Abstract
Spreading and migration of the basal cells neighboring a wound is essential for airway epithelial repair. To gain insight into the molecular mechanisms that govern these cellular processes, we asked whether normal human airway epithelial cells can form podosomes, a cellular structure discovered from cancer and mesenchymal cells that controls migration and invasion. Herein, we report that phorbol-12, 13-dibutyrate (PDBu), a protein kinase C activator, induced reorganization of cytoskeletal structure in primary normal human bronchial epithelial cells, and in normal human airway epithelial BEAS2B cells. Z-stack scanning confocal microscopy showed that PDBu-induced podosome-like structures contain actin-rich columns that arise from the ventral surface of the cell, and also revealed the presence of circular ruffles/waves at the dorsal cell surface. The molecular components of these cytoskeletal structures were determined with immunofluorescent staining. Using in situ zymography, we demonstrated that PDBu-induced podosomes were capable of degrading fibronectin-gelatin-sucrose matrix. PDBu also increased epithelial cell invasion across Transwell chamber. Podosomes and circular dorsal ruffles may be important for epithelial cell migration and invasion, thus contributing to respiratory epithelial repair and regeneration., ((c) 2008 Wiley-Liss, Inc.)
- Published
- 2009
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39. Dissecting the functional domain requirements of cortactin in invadopodia formation.
- Author
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Webb BA, Jia L, Eves R, and Mak AS
- Subjects
- Actins metabolism, Animals, Cell Line, Transformed, Cell Movement, Cell Transformation, Neoplastic genetics, Cell Transformation, Neoplastic metabolism, Cortactin genetics, Extracellular Signal-Regulated MAP Kinases metabolism, Mice, Mutation, NIH 3T3 Cells, Neoplasm Invasiveness, Phenotype, Phosphorylation, Pseudopodia metabolism, RNA Interference, RNA, Small Interfering genetics, RNA, Small Interfering metabolism, Time Factors, Transfection, src-Family Kinases genetics, Cell Surface Extensions metabolism, Cortactin metabolism, Extracellular Matrix metabolism, Fibroblasts metabolism, src Homology Domains genetics, src-Family Kinases metabolism
- Abstract
Cells degrade extracellular matrix (ECM) barriers at focal locations by the formation of membrane protrusions called invadopodia. Polymerization of the actin cytoskeleton is critical to the extension of these processes into the ECM. We used a short interference RNA/rescue strategy to investigate the role of cortactin in the formation of Src-induced invadopodia in 3T3 fibroblasts, and subsequent degradation of the ECM. Cortactin-depleted cells did not form invadopodia or degrade the ECM. Functional invadopodia were restored in cortactin-depleted cells by expression of full-length cortactin, and fragments that contained the intact actin-binding repeats. Mutation of the three Src-targeted Tyr sites to Phe caused a loss in its rescuing ability, while mutation of the Erk phosphorylation sites had little effect on invadopodia formation. Interestingly, knock-down of cortactin did not affect the formation of lamellipodia and only slightly attenuated random cell motility. Our data shows that formation of functional invadopodia requires interaction between cortactin and filamentous actin, while interaction with SH3- and NTA-binding partners plays a less significant role. Furthermore, phosphorylation of cortactin by Src, but not by Erk, is essential for functional invadopodia formation. These results also suggest that cortactin plays a different role in invadopodia-dependent ECM degradation and lamellipodia formation in cell movement.
- Published
- 2007
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40. Phosphorylation of cortactin by p21-activated kinase.
- Author
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Webb BA, Zhou S, Eves R, Shen L, Jia L, and Mak AS
- Subjects
- Animals, Binding Sites, Cells, Cultured, Enzyme Activation, Phosphorylation, Protein Binding, Rats, p21-Activated Kinases, Cortactin chemistry, Cortactin metabolism, Myocytes, Smooth Muscle metabolism, Protein Serine-Threonine Kinases chemistry, Protein Serine-Threonine Kinases metabolism
- Abstract
Cortactin is an F-actin binding protein that is enriched in dynamic cytoskeletal organelles such as podosomes, membrane ruffles, and lamellipodia. We have shown previously that Src-phosphorylation of cortactin is not required for its translocation to phorbol-ester induced podosomes in A7r5 aortic smooth muscle cells, but may be important for stability and turnover of podosomes. However, little is known of the role of Ser/Thr kinases in the regulation of cortactin. Here, we report that p21-associated kinase (PAK), which plays a crucial role in the formation of podosome and membrane ruffles, is able to phosphorylate cortactin in vitro. The predominant phosphorylation site is located at Ser113 in the first actin-binding repeat. Phosphorylation by PAK is not required for the translocation of cortactin to podosomes, lamellipodia, or membrane ruffles in A7r5 smooth muscle cells. However, binding of cortactin to F-actin is significantly reduced by PAK-phosphorylation. Taken together, these results suggest a role for PAK-phosphorylation of cortactin in the regulation of the dynamics of branched actin filaments in dynamic cytoskeletal organelles.
- Published
- 2006
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- View/download PDF
41. Caldesmon is an integral component of podosomes in smooth muscle cells.
- Author
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Eves R, Webb BA, Zhou S, and Mak AS
- Subjects
- Actins metabolism, Animals, Aorta cytology, Calmodulin metabolism, Calmodulin-Binding Proteins genetics, Cell Line, Cytoskeleton metabolism, Fluorescent Dyes metabolism, Myocytes, Smooth Muscle drug effects, Peptide Fragments genetics, Peptide Fragments metabolism, Phorbol 12,13-Dibutyrate pharmacology, Protein Isoforms genetics, Protein Isoforms metabolism, RNA, Small Interfering metabolism, Rats, Recombinant Fusion Proteins genetics, Recombinant Fusion Proteins metabolism, Stress Fibers metabolism, Stress Fibers ultrastructure, Calmodulin-Binding Proteins metabolism, Myocytes, Smooth Muscle cytology, Myocytes, Smooth Muscle metabolism
- Abstract
Podosomes are highly dynamic actin-based structures commonly found in motile and invasive cells such as macrophages, osteoclasts and vascular smooth muscle cells. Here, we have investigated the role of caldesmon, an actin-binding protein, in the formation of podosomes in aortic smooth muscle A7r5 cells induced by the phorbol ester PDBu. We found that endogenous low molecular weight caldesmon (l-caldesmon), which was normally localised to actin-stress fibres and membrane ruffles, was recruited to the actin cores of PDBu-induced podosomes. Overexpression of l-caldesmon in A7r5 cells caused dissociation of actin-stress fibres and disruption of focal adhesion complexes, and significantly reduced the ability of PDBu to induce podosome formation. By contrast, siRNA interference of caldesmon expression enhanced PDBu-induced formation of podosomes. The N-terminal fragment of l-caldesmon, CaD40, which contains the myosin-binding site, did not label stress fibres and was not translocated to PDBu-induced podosomes. Cad39, the C-terminal fragment housing the binding sites for actin, tropomyosin and calmodulin, was localised to stress fibres and was translocated to podosomes induced by PDBu. The caldesmon mutant, CadCamAB, which does not interact with Ca2+/calmodulin, was not recruited to PDBu-induced podosomes. These results show that (1) l-caldesmon is an integral part of the actin-rich core of the podosome; (2) overexpression of l-caldesmon suppresses podosome formation, whereas siRNA knock-down of l-caldesmon facilitates its formation; and (3) the actin-binding and calmodulin-binding sites on l-caldesmon are essential for the translocation of l-caldesmon to the podosomes. In summary, this data suggests that caldesmon may play a role in the regulation of the dynamics of podosome assembly and that Ca2+/calmodulin may be part of a regulatory mechanism in podosome formation.
- Published
- 2006
- Full Text
- View/download PDF
42. Cortactin regulates podosome formation: roles of the protein interaction domains.
- Author
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Webb BA, Eves R, and Mak AS
- Subjects
- Actins drug effects, Animals, Binding Sites, Cell Membrane Structures metabolism, Cells, Cultured, Cortactin genetics, Cortactin metabolism, Liver cytology, Liver metabolism, Muscle, Smooth, Vascular cytology, Muscle, Smooth, Vascular metabolism, Mutagenesis, Site-Directed, Protein Binding physiology, Protein Structure, Tertiary physiology, Rats, Actins metabolism, Cell Membrane Structures physiology, Cortactin physiology
- Abstract
Cortactin, a multi-domain scaffolding protein involved in actin polymerization, is enriched in podosomes induced by phorbol ester in vascular smooth muscle cells. We generated several functional and truncation mutants of cortactin to probe the roles of various protein interaction domains in the regulation of the dynamics of podosome formation. At the onset of podosome genesis, cortactin clustered near the ends of stress fibers that appeared to act as nucleation platforms onto which the actin polymerization machinery assembled. Translocation of cortactin to these pre-podosome clusters required the intact N-WASp-binding SH3 domain. Overexpression of the C-terminal third of cortactin containing the intact SH3 domain inhibited podosome formation presumably by sequestering of N-WASp and prevented cortactin clustering. Subsequent assembly of the actin-rich core of podosomes required translocation of additional cortactin to the actin core, a process that required the actin-binding repeats, but not the Arp2/3-binding N-terminal acidic region nor the SH3 domain. These results suggest that the SH3 domain and the actin-binding repeat region are involved, respectively, in the early and late stages of podosome formation process.
- Published
- 2006
- Full Text
- View/download PDF
43. Effects of tyrosine phosphorylation of cortactin on podosome formation in A7r5 vascular smooth muscle cells.
- Author
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Zhou S, Webb BA, Eves R, and Mak AS
- Subjects
- Animals, Carcinogens metabolism, Cell Line, Cell Shape, Cortactin genetics, Indoles metabolism, Maleimides metabolism, Microscopy, Fluorescence, Phorbol 12,13-Dibutyrate metabolism, Phosphorylation, Protein Kinase C-alpha metabolism, RNA, Small Interfering metabolism, Rats, Sulfonamides metabolism, src-Family Kinases antagonists & inhibitors, src-Family Kinases genetics, src-Family Kinases metabolism, Cell Surface Extensions metabolism, Cortactin metabolism, Muscle, Smooth, Vascular cytology, Myocytes, Smooth Muscle cytology, Myocytes, Smooth Muscle metabolism, Tyrosine metabolism
- Abstract
Cortactin, a predominant substrate of Src family kinases, plays an important role in Arp2/3-dependent actin polymerization in lamellipodia and membrane ruffles and was recently shown to be enriched in podosomes induced by either c-Src or phorbol ester. However, the mechanisms by which cortactin regulates podosome formation have not been determined. In this study, we showed that cortactin is required for podosome formation, using siRNA knockdown of cortactin expression in smooth muscle A7r5 cells. Treatment with phorbol ester or expression of constitutively active c-Src induced genesis of cortactin-containing podosomes as well as increase in phosphorylation of cortactin at Y421 and Y466, the Src phosphorylation sites on cortactin. The Src kinase inhibitor SU-6656 significantly inhibited formation of podosomes induced by phorbol ester and phosphorylation of cortactin, whereas PKCalpha inhibitor did not affect podosome formation in c-Src-transfected cells. Unexpectedly, expression of cortactin mutants containing Y421F, Y421D, Y466F, or Y466D mutated sites did not affect podosome formation or cortactin translocation to podosomes, although endogenous tyrosine-phosphorylated cortactin at Y421 and Y466 was present in podosomes. Our data indicate that 1) PKCalpha acts upstream of Src in phosphorylation of cortactin and podosome formation in smooth muscle cells; 2) expression of cortactin is essential for genesis of podosomes; 3) phosphorylation at Y421 and Y466 is not required for translocation of cortactin to podosomes, although phosphorylation at these sites appears to be enriched in podosomes; and 4) tyrosine phosphorylation of cortactin may be involved in regulation of stability and turnover of podosomes, rather than targeting this protein to the site of podosome formation.
- Published
- 2006
- Full Text
- View/download PDF
44. PAK1 induces podosome formation in A7r5 vascular smooth muscle cells in a PAK-interacting exchange factor-dependent manner.
- Author
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Webb BA, Eves R, Crawley SW, Zhou S, Côté GP, and Mak AS
- Subjects
- Animals, Cell Line, Rats, Rho Guanine Nucleotide Exchange Factors, p21-Activated Kinases, Actin Cytoskeleton physiology, Cell Cycle Proteins physiology, Guanine Nucleotide Exchange Factors physiology, Muscle, Smooth, Vascular ultrastructure, Protein Serine-Threonine Kinases physiology
- Abstract
Remodeling of the vascular smooth muscle cytoskeleton is essential for cell motility involved in the development of diseases such as arteriosclerosis and restenosis. The p21-activated kinase (PAK), which is an effector of the Rho GTPases Rac and Cdc42, has been shown to be involved in cytoskeletal remodeling and cell motility. We show herein that expression of cytoskeletally active constructs of PAK1 is able to induce the formation of dynamic, podosome-like F-actin columns in the A7r5 vascular smooth muscle cell line. Most of these actin columns appear at the junctions between stress fibers and focal adhesions and contain several known podosomal protein markers, such as cortactin, Arp2/3, alpha-actinin, and vinculin. The kinase activity of PAK plays a role in the regulation of the turnover rates of these actin columns but is not essential for their formation. The ability of PAK to interact with the PAK-interacting exchange factor (PIX) but not with Rac or Cdc42, however, is required for the formation of the actin columns as well as for the translocation of PIX and G protein-coupled receptor kinase-interacting protein (GIT) to focal adhesions adjacent to the actin columns. These findings suggest that interaction between PAK and PIX, as well as the recruitment of PIX and GIT to focal adhesions, plays an important role in the formation of actin columns that resemble podosomes induced by phorbol ester in vascular smooth muscle cells.
- Published
- 2005
- Full Text
- View/download PDF
45. Efficacy of a Cancer Research UK communication skills training model for oncologists: a randomised controlled trial.
- Author
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Fallowfield L, Jenkins V, Farewell V, Saul J, Duffy A, and Eves R
- Subjects
- Adult, Clinical Competence, Competency-Based Education, Female, Humans, Male, Medical Oncology standards, Odds Ratio, Prospective Studies, Quality of Health Care, Regression Analysis, United Kingdom, Communication, Medical Oncology education, Physician-Patient Relations
- Abstract
Background: Doctors' communication with patients is commonly hampered by lack of training in this core skill. This study aimed to assess the efficacy of an intensive 3-day training course on communication skills in a randomised controlled trial with a two-by-two factorial design and several outcomes., Methods: 160 oncologists from 34 UK cancer centres were randomly allocated to four groups: written feedback followed by course; course alone; written feedback alone; and control. At each of two assessment periods, consultations with six to ten consecutive, consenting patients per doctor were videotaped. 2407 patients participated. Outcome measures included objective and subjective ratings made by researchers, doctors, and patients. The primary outcomes were objective improvements after the intervention in key communication skills. Course content included structured feedback, videotape review of consultations, role-play with simulated patients, interactive group demonstrations, and discussion led by a trained facilitator., Findings: In Poisson regression analysis of counts of communication behaviours, course attendance significantly improved key outcomes. The estimated effect sizes corresponded to higher rates of use of focused questions (difference between course attenders [n=80] and non-attenders [n=80] 34%, p=0.003), focused and open questions (27%, p=0.005), expressions of empathy (69%, p=0.003), and appropriate responses to patients' cues (38%, p=0.026), and a 24% lower rate of use of leading questions (p=0.11). There was little evidence for the effectiveness of written feedback., Interpretation: The communication problems of senior doctors working in cancer medicine are not resolved by time and clinical experience. This trial shows that training courses significantly improve key communication skills. More resources should be allocated to address doctors' training needs in this vital area.
- Published
- 2002
- Full Text
- View/download PDF
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