scholarly journals Scaling of Subcellular Structures

2020 ◽  
Vol 36 (1) ◽  
pp. 219-236 ◽  
Author(s):  
Wallace F. Marshall
Keyword(s):  
Cell Size ◽  
Cell Type ◽  
Relative Growth ◽  
Measurement Systems ◽  
Active Measurement

As cells grow, the size and number of their internal organelles increase in order to keep up with increased metabolic requirements. Abnormal size of organelles is a hallmark of cancer and an important aspect of diagnosis in cytopathology. Most organelles vary in either size or number, or both, as a function of cell size, but the mechanisms that create this variation remain unclear. In some cases, organelle size appears to scale with cell size through processes of relative growth, but in others the size may be set by either active measurement systems or genetic programs that instruct organelle biosynthetic activities to create organelles of a size appropriate to a given cell type.

scholarly journals Quantitative imaging of intracellular density with ratiometric stimulated Raman scattering microscopy

2021 ◽  
Author(s):  
Benjamin Figueroa ◽  
Fiona Xi Xu ◽  
Ruoqian Hu ◽  
Shuaiqian Men ◽  
Dan Fu
Keyword(s):  
Light Scattering ◽  
Raman Scattering ◽  
Cell Size ◽  
Cell Density ◽  
Cell Function ◽  
Stimulated Raman Scattering ◽  
Cell Types ◽  
Tissue Homeostasis ◽  
Cell Type ◽  
Intact Tissue

AbstractCell size and density impact a wide range of physiological functions, including tissue homeostasis, growth regulation, and osmoregulation. Both are tightly regulated in mammalian cells. In comparison, density variation of a given cell type is much smaller than cell size, indicating that maintenance of cell type-specific density is important for cell function. Despite this importance, little is known about how cell density affects cell function and how it is controlled. Current tools for intracellular cell density measurements are limited either to suspended cells or cells growing on 2D substrates, neither of which recapitulate the physiology of single cells in intact tissue. While optical measurements have the potential to measure cell density in situ and noninvasively, light scattering in multicellular systems prevents direct quantification. Here, we introduce an intracellular density imaging technique based on ratiometric stimulated Raman scattering microscopy (rSRS). It quantifies intracellular drymass density through vibrational imaging of macromolecules. Moreover, water is used as an internal standard to correct for aberration and light scattering. We demonstrate real-time measurement of intracellular density quantification and show that density is tightly regulated across different cell types and can be used to differentiate cell types as well as cell states. We further demonstrate dynamic imaging of density change in response to osmotic challenge as well as intracellular density imaging of a 3D tumor spheroid. Our technique has the potential for imaging intracellular density in intact tissue and understanding density regulation and its role in tissue homeostasis.

scholarly journals Strategies for cellular deconvolution in human brain RNA sequencing data

2020 ◽  
Author(s):  
Olukayode A. Sosina ◽  
Matthew N Tran ◽  
Kristen R Maynard ◽  
Ran Tao ◽  
Margaret A. Taub ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Size ◽  
Expression Profiles ◽  
Brain Regions ◽  
Specific Gene ◽  
Rna Seq ◽  
Cell Type ◽  
Sequencing Data ◽  
Target User ◽  
Size Estimates

AbstractStatistical deconvolution strategies have emerged over the past decade to estimate the proportion of various cell populations in homogenate tissue sources like brain using gene expression data. Here we show that several existing deconvolution algorithms which estimate the RNA composition of homogenate tissue, relates to the amount of RNA attributable to each cell type, and not the cellular composition relating to the underlying fraction of cells. Incorporating “cell size” parameters into RNA-based deconvolution algorithms can successfully recover cellular fractions in homogenate brain RNA-seq data. We lastly show that using both cell sizes and cell type-specific gene expression profiles from brain regions other than the target/user-provided bulk tissue RNA-seq dataset consistently results in biased cell fractions. We report several independently constructed cell size estimates as a community resource and extend the MuSiC framework to accommodate these cell size estimates (https://github.com/xuranw/MuSiC/).

Proportional control of organelle position by a mechanism which similarly monitors cell size of wild type and conical form-mutant Tetrahymena

Development ◽  
1977 ◽  
Vol 42 (1) ◽  
pp. 261-274
Author(s):  
Denis H. Lynn
Keyword(s):  
Cell Size ◽  
Tetrahymena Thermophila ◽  
Cell Length ◽  
Basal Bodies ◽  
Wild Type ◽  
Cell Type ◽  
Cell Width ◽  
Dividing Cells ◽  
Conical Form

Distance between mouthparts of dividing cells of wild type and conical form-mutant Tetrahymena thermophila (formerly T. pyriformis syngen 1) is directly proportional to cell size. This distance is related to cell length in both wild type and conical cells although the proportionality is different in each cell type. However, for both wild type and conical cells the distance between mouthparts is directly and similarly proportional to the product of cell length and cell width which is an estimate of cell size. Evidence has been obtained which suggests that the new mouthparts are positioned with reference to the anterior mouthparts rather than to either pole of the cell. Determination of the site of the new mouthparts is not related to the number of basal bodies between the two sets of mouthparts.

scholarly journals Optimal design of three-dimensional non-uniform nylon lattice structures for selective laser sintering manufacturing

2018 ◽  
Vol 10 (7) ◽  
pp. 168781401879083 ◽  
Author(s):  
Xin Jin ◽  
Guo Xi Li ◽  
Meng Zhang
Keyword(s):  
Mechanical Properties ◽  
Topology Optimization ◽  
Optimal Design ◽  
Cell Size ◽  
Selective Laser Sintering ◽  
Three Dimensional ◽  
Laser Sintering ◽  
Manufacturing Constraints ◽  
Lattice Structures ◽  
Cell Type

As a kind of novel multifunctional structure with three-dimensional pores characterized by low relative density, lattice structures can attain a lightweight design while maintaining high specific mechanical properties in three-dimensional solid structures. Focusing on the challenge of finding the optimal design of lattice structures in the design object, a design and modeling method of non-uniform three-dimensional lattice structures is proposed while ensuring the selective laser sintering manufacturability. Optimization for cell type, cell size, and strut size distribution of lattices is specified with the mechanical properties analyzed and the material model calculated beforehand. The manufacturing constraints are analyzed and expressed in topology optimization and the optimal distribution of topology optimization results is mapped to the strut size distribution of lattice cells. The rapid and automatic computer-aided design modeling of optimized structures is realized by the parametric definition and assembling of lattice components. Finally, the non-uniform structures are successfully manufactured by selective laser sintering and it is shown by means of finite element analysis and experiments that the proposed design approach can improve the mechanical performance compared to the uniform lattice structure under the same weight reduction. And for the design object in this study, body-centered structure with cell size [Formula: see text]mm is chosen as the optimal cell type and cell size under the given selective laser sintering manufacturing constraints.

scholarly journals Fruit growth and sink strength in olive (Olea europaea) are related to cell number, not to tissue size

2020 ◽  
Vol 47 (12) ◽  
pp. 1098
Author(s):  
Adolfo Rosati ◽  
Silvia Caporali ◽  
Sofiene B. M. Hammami ◽  
Inmaculada Moreno-Alías ◽  
Hava Rapoport
Keyword(s):  
Cell Size ◽  
Good Predictor ◽  
Cell Number ◽  
Tissue Growth ◽  
Fruit Growth ◽  
Sink Strength ◽  
Olive Cultivar ◽  
Relative Growth ◽  
Tissue Size ◽  
The Relationship

The relationship between tissue (mesocarp and endocarp) growth and either tissue initial (i.e. in the ovary at bloom) size or cell number was studied using the olive cultivar Leccino (L) and its mutated clone (LC), which produces tetraploid fruits. LC ovaries were 2.7 times the volume of L ovaries, but contained an overall similar number of much larger cells. This allowed decoupling cell number and ovary size, which are normally closely correlated. With this decoupling, cell number in the ovary correlated with tissue growth in the fruit while tissue size in the ovary did not. Cell size in the ovary was inversely correlated with the tissue relative growth from bloom to harvest (i.e. the ratio between final and initial tissue size). These results support the hypothesis that cell number and not tissue size are related to fruit growth and sink strength, and that cell size in the ovary tissues is a good predictor of tissue growth, across cultivars and tissues, even when cell size is strongly affected by ploidy.

Developmental aspects of tristyly in Lythrum salicaria

1998 ◽  
Vol 76 (7) ◽  
pp. 1214-1226 ◽  
Author(s):  
Tarun K Mal
Keyword(s):  
Growth Rate ◽  
Cell Size ◽  
Early Stage ◽  
Lythrum Salicaria ◽  
Growth Patterns ◽  
Epidermal Cells ◽  
Growth Stages ◽  
Relative Growth ◽  
Organ Differentiation ◽  
Intermediate Cells

The developmental basis of floral polymorphism was investigated in the tristylous invasive species, Lythrum salicaria L. (Lythraceae). In tristylous species, the stigmas are positioned above (in the long morph), below (in the short morph), or between (in the mid morph) the outer and inner staminal whorls. Flower samples were collected at three different growth stages (early, pre-anthesis, and post-anthesis) from three genotypes from each of the three morphs to observe morph-specific differences in growth patterns of filaments and styles and their constituent epidermal cells. From each flower, I measured the length of styles and two types of stamens and their epidermal cells at the basal, intermediate, and apical regions of each organ. Differentiation of organ levels begins at a very early stage. Growth rate of the long pistil is higher than in the mid pistil followed by the short pistil. However, the growth rate of epidermal cells is higher in the short style followed by the mid and long styles. The number of cells does not increase during style development in the short morph but does increase in the long and mid morphs. Although the relative growth of the outer stamens is greater than in the inner stamens in all three morphs, the relative cell size is greater in the inner stamens than in the outer stamens. Cell size differs between outer and inner stamens in the long and mid morphs but not in the short morph. The intermediate cells are larger compared with the basal and apical cells of the stamens and styles. The number of epidermal cells increases in the outer stamens during development, whereas it remains constant in the inner stamens of the mid morph and increases only slightly in the inner stamens of long morph.Key words: floral development, growth and division of epidermal cells, heterostyly, purple loosestrife, style and stamen growth, style-stamen polymorphism.

Ultrastructural Correlations between Clonal Human Tumor Colonies and in Vivo Neoplasms

1982 ◽  
Vol 40 ◽  
pp. 210-211
Author(s):  
M.J. Murphy ◽  
R.R. Price ◽  
J.C. Sloman
Keyword(s):  
Cultured Cells ◽  
Human Tumor ◽  
Cell Type ◽  
Tumor Mass ◽  
Initial Cell ◽  
Cloning Assay ◽  
Human Tumor Cloning ◽  
The Relationship

The in vitro human tumor cloning assay originally described by Salmon and Hamburger has been applied recently to the investigation of differential anti-tumor drug sensitivities over a broad range of human neoplasms. A major problem in the acceptance of this technique has been the question of the relationship between the cultured cells and the original patient tumor, i.e., whether the colonies that develop derive from the neoplasm or from some other cell type within the initial cell population. A study of the ultrastructural morphology of the cultured cells vs. patient tumor has therefore been undertaken to resolve this question. Direct correlation was assured by division of a common tumor mass at surgical resection, one biopsy being fixed for TEM studies, the second being rapidly transported to the laboratory for culture.

Some Observations on Changes in Denervated Taste Buds of Circumvallate Papillae of Rabbits

1969 ◽  
Vol 27 ◽  
pp. 308-309
Author(s):  
Sunao Fujimoto ◽  
Raymond G. Murray ◽  
Assia Murray
Keyword(s):  
Taste Buds ◽  
Taste Bud ◽  
Cell Type ◽  
Dark Cells ◽  
Type Iii ◽  
Circumvallate Papillae ◽  
Taste Bud Cells ◽  
Light Cells

Taste bud cells in circumvallate papillae of rabbit have been classified into three groups: dark cells; light cells; and type III cells. Unilateral section of the 9th nerve distal to the petrosal ganglion was performed in 18 animals, and changes of each cell type in the denervated buds were observed from 6 hours to 10 days after the operation.Degeneration of nerves is evident at 12 hours (Fig. 1) and by 2 days, nerves are completely lacking in the buds. Invasion by leucocytes into the buds is remarkable from 6 to 12 hours but then decreases. Their extrusion through the pore is seen. Shrinkage and disturbance in arrangement of cells in the buds can be seen at 2 days. Degenerated buds consisting of a few irregular cells and remnants of degenerated cells are present at 4 days, but buds apparently normal except for the loss of nerve elements are still present at 6 days.

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