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BMC Pediatrics Apr 2013The aim of this study was to revise the 2003 Fenton Preterm Growth Chart, specifically to: a) harmonize the preterm growth chart with the new World Health Organization... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The aim of this study was to revise the 2003 Fenton Preterm Growth Chart, specifically to: a) harmonize the preterm growth chart with the new World Health Organization (WHO) Growth Standard, b) smooth the data between the preterm and WHO estimates, informed by the Preterm Multicentre Growth (PreM Growth) study while maintaining data integrity from 22 to 36 and at 50 weeks, and to c) re-scale the chart x-axis to actual age (rather than completed weeks) to support growth monitoring.
METHODS
Systematic review, meta-analysis, and growth chart development. We systematically searched published and unpublished literature to find population-based preterm size at birth measurement (weight, length, and/or head circumference) references, from developed countries with: Corrected gestational ages through infant assessment and/or statistical correction; Data percentiles as low as 24 weeks gestational age or lower; Sample with greater than 500 infants less than 30 weeks. Growth curves for males and females were produced using cubic splines to 50 weeks post menstrual age. LMS parameters (skew, median, and standard deviation) were calculated.
RESULTS
Six large population-based surveys of size at preterm birth representing 3,986,456 births (34,639 births < 30 weeks) from countries Germany, United States, Italy, Australia, Scotland, and Canada were combined in meta-analyses. Smooth growth chart curves were developed, while ensuring close agreement with the data between 24 and 36 weeks and at 50 weeks.
CONCLUSIONS
The revised sex-specific actual-age growth charts are based on the recommended growth goal for preterm infants, the fetus, followed by the term infant. These preterm growth charts, with the disjunction between these datasets smoothing informed by the international PreM Growth study, may support an improved transition of preterm infant growth monitoring to the WHO growth charts.
Topics: Body Height; Body Weight; Female; Gestational Age; Growth Charts; Head; Humans; Infant; Infant, Newborn; Infant, Premature; Male; Models, Statistical; World Health Organization
PubMed: 23601190
DOI: 10.1186/1471-2431-13-59 -
The New England Journal of Medicine Jul 2008
Review
Topics: Adaptation, Biological; Adult; Birth Weight; Disease; Epigenesis, Genetic; Female; Fetal Development; Gene Expression Regulation; Growth; Health; Humans; Infant; Infant, Newborn; Male; Nutritional Physiological Phenomena; Pregnancy; Prenatal Exposure Delayed Effects; Prenatal Nutritional Physiological Phenomena
PubMed: 18596274
DOI: 10.1056/NEJMra0708473 -
Current Biology : CB Sep 2017Plants are sessile organisms rooted in one place. The soil resources that plants require are often distributed in a highly heterogeneous pattern. To aid foraging, plants... (Review)
Review
Plants are sessile organisms rooted in one place. The soil resources that plants require are often distributed in a highly heterogeneous pattern. To aid foraging, plants have evolved roots whose growth and development are highly responsive to soil signals. As a result, 3D root architecture is shaped by myriad environmental signals to ensure resource capture is optimised and unfavourable environments are avoided. The first signals sensed by newly germinating seeds - gravity and light - direct root growth into the soil to aid seedling establishment. Heterogeneous soil resources, such as water, nitrogen and phosphate, also act as signals that shape 3D root growth to optimise uptake. Root architecture is also modified through biotic interactions that include soil fungi and neighbouring plants. This developmental plasticity results in a 'custom-made' 3D root system that is best adapted to forage for resources in each soil environment that a plant colonises.
Topics: Gravitropism; Phototropism; Plant Roots; Seedlings; Soil
PubMed: 28898665
DOI: 10.1016/j.cub.2017.06.043 -
World Review of Nutrition and Dietetics 2013In mammals, after a period of growth inhibition, body growth often does not just return to a normal rate but actually exceeds the normal rate, resulting in catch-up... (Review)
Review
In mammals, after a period of growth inhibition, body growth often does not just return to a normal rate but actually exceeds the normal rate, resulting in catch-up growth. Recent evidence suggests that catch-up growth occurs because growth-inhibiting conditions delay progression of the physiological mechanisms that normally cause body growth to slow and cease with age. As a result, following the period of growth inhibition, tissues retain a greater proliferative capacity than normal, and therefore grow more rapidly than normal for age. There is evidence that this mechanism contributes both to catch-up growth in terms of body length, which involves proliferation in the growth plate, and to catch-up growth in terms of organ mass, which involves proliferation in multiple nonskeletal tissues.
Topics: Animals; Body Height; Cell Proliferation; Chondrocytes; Growth Plate; Humans; Models, Animal
PubMed: 23428687
DOI: 10.1159/000342535 -
Current Opinion in Microbiology Apr 2015Research into the mechanisms regulating bacterial cell size has its origins in a single paper published over 50 years ago. In it Schaechter and colleagues made the... (Review)
Review
Research into the mechanisms regulating bacterial cell size has its origins in a single paper published over 50 years ago. In it Schaechter and colleagues made the observation that the chemical composition and size of a bacterial cell is a function of growth rate, independent of the medium used to achieve that growth rate, a finding that is colloquially referred to as 'the growth law'. Recent findings hint at unforeseen complexity in the growth law, and suggest that nutrients rather than growth rate are the primary arbiter of size. The emerging picture suggests that size is a complex, multifactorial phenomenon mediated through the varied impacts of central carbon metabolism on cell cycle progression and biosynthetic capacity.
Topics: Bacteria; Biosynthetic Pathways; Cell Cycle; Cell Division; Cell Size
PubMed: 25662920
DOI: 10.1016/j.mib.2015.01.011 -
Current Opinion in Plant Biology Oct 2016In plants, most organs grow post-embryonically through cell division and cell expansion. The coordination of these two growth processes is generally considered to be... (Review)
Review
In plants, most organs grow post-embryonically through cell division and cell expansion. The coordination of these two growth processes is generally considered to be different between dicots and monocots. In dicot plants, such as the model plant Arabidopsis, leaf growth is most often described as being temporally regulated with cell division ceasing earlier at the tip and continuing longer at the base of the leaf. Conversely, in monocot leaves, the organization of the growth processes is rather viewed as spatially regulated with dividing cells at the base of the leaf, followed by expanding cells and finally mature cells at the tip. As our understanding of the leaf growth processes in the two major classes of flowering plants expands, it becomes increasingly clear that the regulation of the growth processes is to a great extent conserved between dicots and monocots. In this review, we highlight how the temporal and spatial organization of cell division and cell expansion takes place in both dicot and monocot leaves. We also show that there are similarities in the molecular wiring that coordinates these two processes during leaf development.
Topics: Cell Cycle; Cell Division; Magnoliopsida; Phylogeny; Plant Leaves; Species Specificity
PubMed: 27344391
DOI: 10.1016/j.pbi.2016.06.009 -
Current Opinion in Plant Biology Feb 2008Cell-cell communication is essential for growth and development of multicellular organisms. In higher plants, the shoot organs are derived from three clonally distinct... (Review)
Review
Cell-cell communication is essential for growth and development of multicellular organisms. In higher plants, the shoot organs are derived from three clonally distinct cell layers present in the meristem. The role of the outermost L1 cell layer and its derived epidermis in coordinating growth of the inner-cell layers has long been debated. This question has been revisited recently using molecular tools to manipulate cell cycle progression or cell expansion, specifically in the epidermis. These studies conclude that cells in the epidermis both promote and restrict growth of the entire shoot by sending growth signals - either physical or chemical - to the inner layers.
Topics: Cell Communication; Cell Division; Cell Enlargement; Cell Proliferation; Chimera; Plant Epidermis; Plant Growth Regulators; Plant Shoots
PubMed: 18065257
DOI: 10.1016/j.pbi.2007.10.009 -
Trends in Plant Science Dec 2019Size is a fundamental property that must be tightly regulated to ensure that cells and tissues function efficiently. Dynamic size control allows unicellular organisms to... (Review)
Review
Size is a fundamental property that must be tightly regulated to ensure that cells and tissues function efficiently. Dynamic size control allows unicellular organisms to adapt to environmental changes, but cell size is also integral to multicellular development, affecting tissue size and structure. Despite clear evidence for homeostatic cell size maintenance, we are only now beginning to understand cell size regulation in the actively dividing meristematic tissues of higher plants. We discuss here how coupled advances in live cell imaging and modelling are uncovering dynamic mechanisms for size control mediated at the cellular level. We argue that integrated models of cell growth and division will be necessary to predict cell size and fully understand multicellular growth and development.
Topics: Cell Cycle; Cell Division; Cell Proliferation; Cell Size; Meristem
PubMed: 31630972
DOI: 10.1016/j.tplants.2019.09.005 -
Poultry Science Apr 2021Broiler growth performance can be influenced by maternal BW, maternal age, and sex. The present study evaluated broiler growth and efficiency in response to increased...
Broiler growth performance can be influenced by maternal BW, maternal age, and sex. The present study evaluated broiler growth and efficiency in response to increased maternal BW (relaxed level of maternal feed restriction). It was hypothesized that BW and fatness would increase, and efficiency would be reduced as maternal BW increased. Ten BW trajectories were applied to precision-fed Ross 708 female broiler breeders (n = 30) from 2 to 42 wk of age. Trajectories varied in prepubertal and pubertal growth phases from 2.5 to 22.5% above the recommended BW target. Additional unrestricted breeders (n = 6) were not limited to a maximum BW (fed ad libitum). Two 35 d experiments were conducted with precision-fed broilers from these breeders at 35 and 42 wk of age. Two analyses (full and restricted analysis scopes) were performed to evaluate broiler BW, feed conversion ratio (FCR) and carcass traits with maternal BW at photostimulation (22 wk of age) as a continuous effect, and maternal age and sex as discrete effects. The full scope included broilers from all hens (feed restricted and unrestricted). The restricted scope excluded broilers from unrestricted hens. Differences were reported at P ≤ 0.05. For every kilogram increase in maternal BW, cumulative FCR increased by 0.235 and 0.471 g:g for broilers from all and feed restricted hens, respectively. Proportional gut weight of broilers from feed restricted hens decreased by 0.8244% per kilogram increase in maternal BW. Males were heavier than females on day 28 and 35, and broilers from 42-wk-old breeders were heavier than broilers from 35-wk-old breeders on day 0 and 35. Males from all hens were more feed efficient (1.318 g:g) than females (1.335 g:g) from day 29 to 35. Females from all and feed restricted hens had a greater proportional fat pad and breast muscle weight than males, and proportional breast muscle yield of broilers from 42-wk-old breeders was on average 1.04 times greater than that of broilers from 35-wk-old breeders. Maternal BW did not affect offspring BW, reduced cumulative FCR, and reduced gut weight in the restricted analysis scope.
Topics: Adipose Tissue; Animal Feed; Animals; Body Weight; Chickens; Diet; Energy Metabolism; Feeding Methods; Female; Growth; Male
PubMed: 33610891
DOI: 10.1016/j.psj.2021.01.016 -
Birth Defects Research Jul 2018Physiologically based pharmacokinetic (PBPK) models are developed from compound-independent information to describe important anatomical and physiological...
Physiologically based pharmacokinetic (PBPK) models are developed from compound-independent information to describe important anatomical and physiological characteristics of an individual or population of interest. Modeling pediatric populations is challenging because of the rapid changes that occur during growth, particularly in the first few weeks and months after birth. Neonates who are born premature pose several unique challenges in PBPK model development. To provide appropriate descriptions for body weight (BW) and height (Ht) for age and appropriate incremental gains in PBPK models of the developing preterm and full term neonate, anthropometric measurements collected longitudinally from 1,063 preterm and 158 full term neonates were combined with 2,872 cross-sectional measurements obtained from the NHANES 2007-2010 survey. Age-specific polynomial growth equations for BW and Ht were created for male and female neonates with corresponding gestational birth ages of 25, 28, 31, 34, and 40 weeks. Model-predicted weights at birth were within 20% of published fetal/neonatal reference standards. In comparison to full term neonates, postnatal gains in BW and Ht were slower in preterm subgroups, particularly in those born at earlier gestational ages. Catch up growth for BW in neonates born at 25, 28, 31, and 34 weeks gestational age was complete by 13, 8, 6, and 2 months of life (males) and by 10, 6, 5, and 2 months of life (females), respectively. The polynomial growth equations reported in this paper represent extrauterine growth in full term and preterm neonates and differ from the intrauterine growth standards that were developed for the healthy unborn fetus.
Topics: Body Height; Body Weight; Child, Preschool; Female; Gestational Age; Growth and Development; Humans; Infant; Infant, Newborn; Infant, Premature; Longitudinal Studies; Male; Premature Birth; Reference Standards
PubMed: 29536674
DOI: 10.1002/bdr2.1214