Pattern as a function of cell number and cell size on the second-leg basitarsus ofDrosophila

1979 ◽  
Vol 187 (2) ◽  
pp. 105-127 ◽  
Author(s):  
Lewis Irving Held
Keyword(s):  
Diabetologia ◽  
2021 ◽  
Author(s):  
Hironobu Sasaki ◽  
Yoshifumi Saisho ◽  
Jun Inaishi ◽  
Yuusuke Watanabe ◽  
Tami Tsuchiya ◽  
...  

Abstract Aims/hypothesis Type 2 diabetes is characterised by reduced beta cell mass (BCM). However, it remains uncertain whether the reduction in BCM in type 2 diabetes is due to a decrease in size or number of beta cells. Our aim was to examine the impact of beta cell size and number on islet morphology in humans with and without type 2 diabetes. Methods Pancreas samples were obtained from 64 Japanese adults with (n = 26) and without (n = 38) type 2 diabetes who underwent pancreatectomy. Using pancreatic tissues stained for insulin, we estimated beta cell size based on beta cell diameter. Beta cell number was estimated from the product of fractional beta cell area and pancreas volume divided by beta cell size. The associations of beta cell size and number with islet morphology and metabolic status were examined. Results Both beta cell size (548.7 ± 58.5 vs 606.7 ± 65.0 μm3, p < 0.01) and number (5.10 × 108 ± 2.35 × 108 vs 8.16 × 108 ± 4.27 × 108, p < 0.01) were decreased in participants with type 2 diabetes compared with those without diabetes, with the relative reduction in beta cell number (37%) being greater than for beta cell size (10%). Beta cell number but not size was positively correlated with BCM in participants with and without type 2 diabetes (r = 0.97 and r = 0.98, both p < 0.01) and negatively correlated with HbA1c (r = −0.45, p < 0.01). Conclusions/interpretation Both beta cell size and number were reduced in participants with type 2 diabetes, with the relative reduction in beta cell number being greater. Decrease in beta cell number appears to be a major contributor to reduced BCM in type 2 diabetes. Graphical abstract


2004 ◽  
Vol 129 (1) ◽  
pp. 37-41 ◽  
Author(s):  
Yahya K. Al-Hinai ◽  
Teryl R. Roper

The effects of rootstock on growth of fruit cell number and size of `Gala' apple trees (Malus domestica Borkh) were investigated over three consecutive seasons (2000-02) growing on Malling 26 (M.26), Ottawa-3, Pajam-1, and Vineland (V)-605 rootstocks at the Peninsular Agricultural Research Station near Sturgeon Bay, WI. Fruit growth as a function of cell division and expansion was monitored from full bloom until harvest using scanning electron microscopy (SEM). Cell count and cell size measurements showed that rootstock had no affect on fruit growth and final size even when crop load effects were removed. Cell division ceased about 5 to 6 weeks after full bloom (WAFB) followed by cell expansion. Fruit size was positively correlated (r2 = 0.85) with cell size, suggesting that differences in fruit size were primarily a result of changes in cell size rather than cell number or intercellular space (IS).


Author(s):  
A. SELAMAT ◽  
S. A. ATIMAN ◽  
A. PUTEH ◽  
N. A. P. ABDULLAH ◽  
M. T. M. MOHAMED ◽  
...  

Kangkong, especially the upland type (Ipomoea reptans) is popularly consumed as a vegetable dish in the South East Asian countries for its quality related to Vitamins (A and C) and crude fiber contents. Higher fiber contents would prevent from the occurrence of colon cancer and diverticular disease. With young stem edible portion, its cell number and size contribute to the stem crude fiber content. The mathematical approach of allometry of cell size, number, and fiber content of stem could be used in determining the 'best' plant density pressure in producing the quality young stem to be consumed. Basically, allometry is the ratio of relative increment (growth or change) rates of two parameters, or the change rate associated to the log of measured variables relationship. Kangkog grown equal or lower than 55 plants m-2 produced bigger individual plant and good quality (physical) kangkong leafy vegetable, but with lower total yield per unit area as compared to those grown at higher densities.


1984 ◽  
Vol 11 (6) ◽  
pp. 553 ◽  
Author(s):  
ME Nicolas ◽  
RM Gleadow ◽  
MJ Dalling

The effects of two levels of temperature and of water supply on grain development of wheat (cv. Warigal) were studied by imposing treatments during the early or late period of cell division. High temperature (28°C day/20°C night) accelerated development of the grain. Dry matter accumulation and cell division proceeded at a higher rate but had a shorter duration in the high temperature treatments. Maximum cell number, final cell size and the number of large starch granules per cell were not significantly reduced by high temperature. Drought and drought × high temperature reduced the storage capacity of the grain, with a decrease in number of cells and starch granules in the endosperm. Cell size was also reduced when treatments were imposed late during cell division. Duration of dry matter accumulation and cell division was reduced in the drought and drought × high temperature treatments. The combined effects of drought and high temperature were much more severe than those of each separate treatment. The amount of sucrose per cell was similar in all treatments. It appears unlikely that the supply of sucrose to the endosperm cells is the main limiting factor of dry matter accumulation in both drought and high temperature treatments.


1996 ◽  
Vol 271 (6) ◽  
pp. L910-L917 ◽  
Author(s):  
P. N. Black ◽  
P. G. Young ◽  
S. J. Skinner

Transforming growth factor-beta (TGF-beta) is formed in the airways and may have a role in airway remodeling in asthma. We have studied the effects of TGF-beta on bovine airway smooth muscle cells (BASMC) in vitro. Thymidine incorporation by BASMC was inhibited after a 24-h incubation with TGF-beta 1. In contrast, thymidine incorporation by BASMC was stimulated (35.1 +/- 11.2%) after a 48-h incubation with 1 ng/ml TGF-beta 1. Cell number was also increased (25.9 +/- 7.6%) after a 72-h incubation with 3 ng/ml TGF-beta 1. TGF-beta 1 also increased cell size at 72 h, with a 24.3 +/- 6.2% increase in cell, diameter. Increases in BASMC size were accompanied by increased [3H]proline incorporation into cell protein. In cells from any individual animal, there was a strong inverse correlation (r = -0.97) between changes in cell number and cell size. In cells from some animals, the main effect of TGF-beta 1 was to promote an increase in cell number, whereas in others the predominant effect was cell hypertrophy. In contrast epidermal growth factor (EGF) led to an increase in thymidine incorporation and cell number in all preparations but did not increase cell size. TGF-beta 1 also promoted secretion of glycosaminoglycans into culture medium by BASMC with a preferential increase in hyaluronan secretion (4.5-fold) after 24 h. Latent TGF-beta (0.89 +/- 0.06 ng/ml) was also detected in conditioned medium from cultured BASMC, and TGF-beta 1 expression was demonstrated with RNA extracts from BASMC. Varying degrees of both smooth muscle cell hypertrophy and hyperplasia occur in asthma. These results obtained with airway smooth muscle cells indicate that TGF-beta could play a role in the structural changes seen in asthma.


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