The relative significance of growth rate and interdivision time in the size control of cultured mammalian epithelial cells

1987 ◽  
Vol 88 (1) ◽  
pp. 73-80
Author(s):  
M. Hola ◽  
P.A. Riley
Keyword(s):  
Growth Rate ◽  
Epithelial Cells ◽  
Cell Size ◽  
Negative Correlation ◽  
Average Rate ◽  
Growth Period ◽  
Time Lapse ◽  
Relative Significance ◽  
Initial Volume ◽  
The Mean

Genealogies of a line of mammalian epithelial cells (GPK) have been constructed from time-lapse film of monolayer cultures and measurements made of initial (post-divisional) cell size, final (pre-divisional) cell size and interdivision time (IDT). The mean initial cell volume was 2696 +/− 404 (S.D.) micron3, the mean final volume was 5247 +/− 696 micron3 and the mean IDT was 985 +/− 84 min. Cell size regulation must be by modulation of either the growth rate or the length of the growth period. Increase in size was strongly correlated with the average rate of growth (increase in volume per unit time) (R = 0.94, P much less than 0.001), whilst no correlation was found between increase in size and IDT. Although a negative correlation was found between initial volume and IDT (P less than 0.02), this appeared to be due to differences in IDT between sister cells being correlated with differences in their initial volumes (P less than 0.02), as indicated by the lack of correlation between mean sister IDT and mean sister initial volume. The regulatory effect of growth rate was demonstrated by a negative correlation between growth rate and the initial volume of the cell (P less than 0.005), which is independent of differences between siblings. The mean growth rate of sibling cells was found to be negatively correlated with both the maternal growth rate (P less than 0.01) and the maternal volume increase (P less than 0.005). This implies that the growth rate of division products (which manifest similar growth rates) is influenced by the growth of the progenitor cell.

Variation in rectal temperature of cattle in a tropical environment and its relation to growth rate

1984 ◽  
Vol 38 (3) ◽  
pp. 417-427 ◽  
Author(s):  
H. G. Turner
Keyword(s):  
Growth Rate ◽  
Genetic Correlation ◽  
Rectal Temperature ◽  
Bos Indicus ◽  
Heritability Estimate ◽  
Growth Period ◽  
The Other ◽  
Tropical Environment ◽  
The Mean ◽  
Selection Of

ABSTRACTRectal temperatures of cattle grazed near the tropic of Capricorn in central Queensland were studied. The cattle were of Bos indicus, B. taurus and crossbred lines, and were represented by over 200 growing heifers in each of 2 years and some supplementary groups.Rectal temperatures were loge normally distributed when they were expressed as deviations from a basal temperature of 38°C. They were significantly repeatable, but were more highly repeatable when herd mean temperature was above 39·5°C. The heritability estimate was 0·33 (P < 0·01).The mean phenotypic regression of growth rate on rectal temperature, within breed groups, was 0·04 (s.e. 0·006) kg/day per °C (r = 0·3, P < 0·01) over the entire growth period from birth to 18 months of age but greater during warmer seasons. The estimated genetic correlation was insignificant in one group of heifers but −0·86 (s.e. 0·17) in the other.The evidence of favourable and possible unfavourable responses to selection of cattle for low rectal temperature in warm environments is discussed.

scholarly journals THE GROWTH AND DURATION OF LIFE OF CELOSIA CRISTATA SEEDLINGS AT DIFFERENT TEMPERATURES

1934 ◽  
Vol 17 (6) ◽  
pp. 763-781 ◽  
Author(s):  
Thomas I. Edwards ◽  
Raymond Pearl ◽  
Sophia A. Gould
Keyword(s):  
Growth Rate ◽  
Maximum Yield ◽  
Total Duration ◽  
Growth Curves ◽  
Growth Period ◽  
Hypocotyl Length ◽  
Rate Of Growth ◽  
Life Duration ◽  
Celosia Cristata ◽  
The Mean

Daily measurements of hypocotyl length were made on Celosia cristata seedlings cultured in darkness under aseptic conditions at six constant temperatures between 14.5° and 40.5°C. At 40.5° roots did not penetrate the agar and only the hypocotyls that were supported by the wall of the test tube could be measured. The growth curves were of the generalized logistic type, but of different degrees of skewness. The degree of symmetry of the growth curves was influenced by temperature. At the lower temperatures the maximal growth rate came relatively late in the grand period of growth; at successively higher temperatures it came progressively earlier. The mean total time rate of growth (millimeter per diem) was found to be a parabolic function of the temperature. The maximum rate of growth was found from the curve to be at 30.48°C. The maximum observed rate of growth, and the maximum yield, were found to be at 30°C. At all temperatures above 14.5° the maximum growth activity fell in the second quarter of the whole growth period. At all temperatures tested other than 30°, and at all parts of the growth cycle, the growth yield as measured by height of hypocotyl at any given equivalent point was less than at 30°. The total duration of life of the seedlings, and the duration of life after the end of the growth period (intermediate period) were inversely proportional to the mean total growth rate. The observations on Celosia cristata seedlings are thus in accord with the "rate of living" theory of life duration. The optimal temperature for life duration is the minimum temperature, within the range of these observations.

A study of the growth rate of F2 and F3 Africander cross, Brahman cross and British cross cattle from birth to 18 months in a tropical environment

1971 ◽  
Vol 11 (53) ◽  
pp. 593 ◽  
Author(s):  
JF Kennedy ◽  
GIK Chirchir
Keyword(s):  
Growth Rate ◽  
Rank Order ◽  
Growth Period ◽  
Dry Season ◽  
Tropical Environment ◽  
Wet Season ◽  
Male And Female ◽  
The Mean

The mean birthweights and weaning weights of approximately 1200 male and female calves of the F2 and F3 generations of Africander cross (AX), Brahman cross (BX) and Shorthorn X Hereford cross (SH) cattle, together with the weights at four months, and nine months post weaning for approximately 500 of the females, for the years 1964-1968, are presented. BX calves (29.7 kg) were lighter at birth than AX (31.0 kg) or SH (31.8 kg), but at weaning (eight-nine months) they were 13.7 kg heavier than the AX, and 28.9 kg heavier than the SH. In the first four months postweaning, at the end of the dry-season, female AX gained 21.5 kg, BX gained 18.5 kg, and the SH 11.7 kg, and in the next five months, which included the wet-season, AX gained 78.6 kg, BX 83.1 kg, and SH 63.2 kg. At approximately eighteen months old the AX weighed 282.8 kg, BX 294.8 kg, and SH 244.2 kg. There were substantial differences between years but the rank order of the breeds at each growth period did not change.

Correlation of Human Arterial Morphology With Hemodynamic Measurements in Arterial Casts

1981 ◽  
Vol 103 (3) ◽  
pp. 204-207 ◽  
Author(s):  
M. H. Friedman ◽  
G. M. Hutchins ◽  
C. B. Bargeron ◽  
O. J. Deters ◽  
F. F. Mark
Keyword(s):  
Shear Rate ◽  
Cross Section ◽  
Negative Correlation ◽  
Average Rate ◽  
Laser Doppler Anemometer ◽  
Aortic Bifurcation ◽  
Fluid Velocities ◽  
The Mean ◽  
Time Average ◽  
Hemodynamic Measurements

A realistic pulsatile flow was passed through a cast of the aortic bifurcation of a 63-yr-old male with mild atherosclerosis, and a laser Doppler anemometer was used to measure fluid velocities in the cast at 15 selected sites near the lateral and medial walls. Intimal, medial and adventitial thicknesses were measured and sudanophilia was scored at corresponding sites in the vessel from which the cast had been made. A negative correlation was found between intimal thickness (IT) and wall shear rate. The strongest negative correlation (p<0.005) was between IT and “pulse shear rate” (PSR), defined by analogy with pulse pressure. Sudanophilia also correlated negatively with PSR (p<0.01). Medial thickness correlated positively with shear rate, and most strongly with the mean (i.e., time-average) rate (p<0.005). From an analysis of the fluid mechanical data, it appears possible to separate the effects of bifurcation geometry and the shape of the arterial cross section on inter facial shear.

scholarly journals Environmental impacts on single-cell variation within a ubiquitous diatom: The role of growth rate

PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0251213
Author(s):  
Elisabeth Groß ◽  
Maarten Boersma ◽  
Cédric Léo Meunier
Keyword(s):  
Growth Rate ◽  
Phenotypic Plasticity ◽  
Global Change ◽  
Single Cell ◽  
Cell Size ◽  
Negative Correlation ◽  
Growth Rates ◽  
N:P Ratio ◽  
Future Scenario ◽  
Trait Variability

Morphological and physiological characteristics of phytoplankton cells are highly sensitive to changes in environmental conditions and, in turn, influence the dynamics of phytoplankton populations and communities. To cope with environmental change, trait variability and phenotypic plasticity may play an important role. Since global change comprises simultaneous changes in abiotic parameters, we assessed the impact of multiple drivers on functional traits of the diatom Thalassiosira (Conticribra) weissflogii by manipulating concurrently temperature, pCO2, and dissolved nitrogen:phosphorus (N:P) ratio. We tested three scenarios: ambient (ambient temperature and atmospheric pCO2; 16 N:P ratio), moderate future scenario (+1.5°C and 800 ppm CO2; 25 N:P ratio), and more severe future scenario (+3°C and 1000 ppm CO2; 25 N:P ratio). We applied flow cytometry to measure on single-cell levels to investigate trait variability and phenotypic plasticity within one strain of diatoms. Growth rates differed significantly between the treatments and were strongly correlated with cell size and cellular chlorophyll a content. We observed a negative correlation of growth rate with chlorophyll a variability among single strain populations and a negative correlation with the phenotypic plasticity of cell size, i.e. when growth rates were higher, the cell size cell-to-cell variability within cultures was lower. Additionally, the phenotypic plasticity in cell size was lower under the global change scenarios. Overall, our study shows that multiple traits are interlinked and driven by growth rate and that this interconnection may partly be shaped by environmental factors.

scholarly journals Cell size sensing in animal cells coordinates anabolic growth rates with cell cycle progression to maintain uniformity of cell size

2017 ◽  
Author(s):  
Miriam B. Ginzberg ◽  
Nancy Chang ◽  
Ran Kafri ◽  
Marc W. Kirschner
Keyword(s):  
Cell Cycle ◽  
Growth Rate ◽  
Cell Size ◽  
Growth Rates ◽  
Cell Cycle Progression ◽  
Time Lapse ◽  
Small Cells ◽  
Live Cells ◽  
Control Mechanisms ◽  
Animal Cells

AbstractThe uniformity of cell size in healthy tissues suggests that control mechanisms might coordinate cell growth and division. We derived a method to assay whether growth rates of individual cells depend on cell size, by combining time-lapse microscopy and immunofluorescence to monitor how variance in cell size changes as cells grow. This analysis revealed two periods in the cell cycle when cell size variance decreases in a manner incompatible with unregulated growth, suggesting that cells sense their own size and adjust their growth rate to correct aberrations. Monitoring nuclear growth in live cells confirmed that these decreases in variance reflect a process that selectively inhibits the growth of large cells while accelerating growth of small cells. We also detected cell-size-dependent adjustments of G1 length, which further reduce variability. Combining our assays with chemical and genetic perturbations confirmed that cells employ two strategies, adjusting both cell cycle length and growth rate, to maintain the appropriate size.

scholarly journals Mean daily growth of herring larvae in relation to temperature over a range of 5–20°C, based on weekly repeated cruises in the Greifswalder Bodden

2009 ◽  
Vol 66 (8) ◽  
pp. 1696-1701 ◽  
Author(s):  
Rainer Oeberst ◽  
Mark Dickey-Collas ◽  
Richard D. M. Nash
Keyword(s):  
Growth Rate ◽  
Significant Influence ◽  
Temperature Increase ◽  
Size Range ◽  
Larval Growth ◽  
Growth Period ◽  
Large Temperature ◽  
Daily Growth ◽  
Temperature Range ◽  
The Mean

Abstract Oeberst, R., Dickey-Collas, M., and Nash, R. D. M. 2009. Mean daily growth of herring larvae in relation to temperature over a range of 5–20°C, based on weekly repeated cruises in the Greifswalder Bodden. – ICES Journal of Marine Science, 66: 1696–1701. Reported estimates of mean daily growth of herring larvae generally cover the temperature range 1–12°C and few estimates are available for temperatures >15°C. We use larval surveys on Rügen spring-spawning herring in the Strelasund and the Greifswalder Bodden to estimate larval growth over a wider temperature range because the water temperature in that area normally increases from 5 to 20°C during the larval growth period (i.e. from spring to summer). This large temperature increase has a significant influence on the mean daily growth of herring larvae. Growth estimates were based on the modes of length frequencies observed at individual stations or accumulated over strata from consecutive surveys. Mean daily growth (G; mm d−1) of larvae was primarily determined by the ambient temperature (T) during the growth interval (5–7 d), resulting in the following relationship: G = 0.011 + 0.037 T. A non-linear function is also described. Growth rate was not length-dependent over the size range studied (5–20 mm). The study also showed that herring larvae were growing and surviving in temperatures up to 17.5°C.

THE RATE OF DRY WEIGHT ACCUMULATION IN MARQUIS WHEAT AS AFFECTED BY TEMPERATURE AND LIGHT INTENSITY

1962 ◽  
Vol 40 (7) ◽  
pp. 939-955 ◽  
Author(s):  
D. J. C. Friend ◽  
V. A. Helson ◽  
J. E. Fisher
Keyword(s):  
Growth Rate ◽  
Light Intensity ◽  
Relative Growth Rate ◽  
Growth Period ◽  
Dry Weight ◽  
Continuous Illumination ◽  
Relative Growth ◽  
Absolute Growth Rate ◽  
Absolute Growth ◽  
The Mean

Plants were grown to the stage of anthesis at constant temperatures from 10 to 30 °C and under continuous illumination at intensities ranging from 200 to 2500 ft-c. The absolute growth rate was maximal at the time of ear emergence. The relative growth rate declined continuously with time; the rate of decline was greatest at the higher temperatures and light intensities. The optimal temperature for the mean absolute growth rate over the whole growth period was 20–25 °C. The optimum for the mean relative growth rate was 15–20 °C. This difference is attributed to the faster rate of floral development at high temperatures. Both absolute and relative growth rates increased with increasing light intensity up to 2500 ft-c.

RELATIONSHIP BETWEEN CARDIOVASCULAR DISEASES AND ANATOMOSIS OF ARTERIOVENOUS FISTULAR IN PATIENTS WITH REGULARLY HEMODIALYSIS

2017 ◽  
pp. 88-92
Author(s):  
Van Hien Pham ◽  
Huu Vu Quang Nguyen ◽  
Tam Vo
Keyword(s):  
Heart Failure ◽  
Blood Pressure ◽  
Renal Failure ◽  
Chronic Renal Failure ◽  
Cardiovascular Diseases ◽  
Systolic Blood Pressure ◽  
Diastolic Blood Pressure ◽  
Negative Correlation ◽  
Mean Value ◽  
The Mean

Background: Cardiovascular diseases are the leading cause of death in patients with chronic renal failure. When a patient undergoes dialysis, making AVF or AVG causes cardiovascular events. Understanding the relationship between complications: hypertension, heart failure, AVF or AVG (formation time, position, diameter) helps us monitor, detect, prevent and treatment of complications to limit the risk of death in patients with dialysis. Objective: Relationship between cardiovascular diseases and anatomosis of arteriovenous fistular in patients with regularly hemodialysis at Cho Ray Hospital. Methods: A cross-sectional study was conducted at Cho Ray Hospital from 2015 to 2016. The survey some cardiovascular diseases are done by clinical examination, tests for diagnostic imaging such as X-ray, electrocardiogram and echocardiogram: heart and diameter of anastomosis AVF, AVG. Results: The study population included 303 patients with chronic renal failure who were dialysis. Of which, patients aged 25-45 accounted for the highest proportion (43.9%). The proportion of male and female patients was similar (48.5% and 51.5% respectively). The mean value of systolic blood pressure on patients made AVF, AVG less than 12 months is higher than patients made AVF, AVG over 12 months, and there is negative correlation (r = -0.43) between AVF, AVG and systolic blood pressure (p <0.05). The mean value of diastolic blood pressure on patients made AVF, AVG less than 12 months is lower than patients made AVF, AVG over 12 months, and and there is positive correlation (r = -0.43) between AVF, AVG and diastolic blood pressure (p <0.05) (p <0.05). The prevalence of patients with heart failure made AVF, AVG over 12 months is higher than that of the under 12 months group, there is a negative correlation (r = - 0.43) between AVF, AVG diameter and EF index (p <0.05). Conclusion: It is important to note the diameter of anastomosis AVF, AVG in patients with chronic renal failure dialysis to limit cardiovascular complications, especially heart failure. Key words: Chronic kidney disease, hemodialysis.

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