Cell lineage has been used to explain the stomatal distribution in several plant species. We have used transgenic plants carrying a 35SGUS::Ac construct that produces clonal sectors to analyze the possible role of cell lineage during the establishment of stomatal patterning in Arabidopsis leaves. The analysis of sectors ranging from two to eighteen cells supports the conclusion that most stomatal complexes derive from a single and immediate precursor cell through a stereotyped pattern of three unequal cell divisions followed by a final equal one. In addition, it shows that the successive cell divisions take place at a constant angle (approximately 60 degrees ) with respect to the previous one. Interestingly, this angular dimension shifts from 60 degrees to 0 degrees in the last cell division that gives rise to the stoma. These sectors also reveal the development of both clockwise and counterclockwise patterns of cell divisions during stomatal development in approximately equal numbers. Our clonal analysis indicates that cell divisions involved in the development of stomatal complexes are probably the last ones contributing to epidermal growth and development. Finally, the stereotyped pattern of cell divisions that culminates in the formation of stomatal complexes indicates that cell lineage plays a very important role during stomatal pattern establishment.
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http://dx.doi.org/10.1006/dbio.2001.0506 | DOI Listing |
JAMA Netw Open
January 2025
Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, Maryland.
Importance: Sensitivity to environmental stress and adversity may influence lung cancer risk, highlighting a critical link between psychosocial factors and cancer etiology.
Objective: To evaluate whether genetically estimated sensitivity to environmental stress and adversity is associated with lung cancer risk.
Design, Setting, And Participants: Data were obtained from a genome-wide association study identifying 37 independent genetic variants strongly associated with sensitivity to environmental stress and adversity and a cross-ancestry genome-wide meta-analysis from the International Lung Cancer Consortium.
J Comput Neurosci
January 2025
Computational Brain Science Lab, Division of Computational Science and Technology, KTH Royal Institute of Technology, SE-100 44, Stockholm, Sweden.
This paper presents an in-depth theoretical analysis of the orientation selectivity properties of simple cells and complex cells, that can be well modelled by the generalized Gaussian derivative model for visual receptive fields, with the purely spatial component of the receptive fields determined by oriented affine Gaussian derivatives for different orders of spatial differentiation. A detailed mathematical analysis is presented for the three different cases of either: (i) purely spatial receptive fields, (ii) space-time separable spatio-temporal receptive fields and (iii) velocity-adapted spatio-temporal receptive fields. Closed-form theoretical expressions for the orientation selectivity curves for idealized models of simple and complex cells are derived for all these main cases, and it is shown that the orientation selectivity of the receptive fields becomes more narrow, as a scale parameter ratio , defined as the ratio between the scale parameters in the directions perpendicular to vs.
View Article and Find Full Text PDFEnviron Toxicol Chem
January 2025
Institute for Environmental Health Solutions, Gillings School of Global Public Health, University of North Carolina, NC, United States.
Hum Cell
January 2025
Department of Tumor Pathology, Faculty of Medical Sciences, University of Fukui, 23-3 Matsuoka-Shimoaizuki, Eiheiji, Fukui, 910-1193, Japan.
Only a few human ovarian endometrioid carcinoma cell lines are currently available, partly due to the difficulty of establishing cell lines from low-grade cancers. Here, using a cell immortalization strategy consisting of i) inactivation of the p16-pRb pathway by constitutive expression of mutant cyclin-dependent kinase 4 (R24C) (CDK4) and cyclin D1, and ii) acquisition of telomerase reverse transcriptase (TERT) activity, we established a human ovarian endometrioid carcinoma cell line from a 46-year-old Japanese woman. That line, designated JFE-21, has proliferated continuously for over 6 months with a doubling time of ~ 55 h.
View Article and Find Full Text PDFNaunyn Schmiedebergs Arch Pharmacol
January 2025
Division of Nephrology, Faculty of Medicine, Department of Internal Medicine, Suleyman Demirel University, Isparta, Turkey.
The kidneys have a regulatory role in many diseases with their diuresis function and capacity to maintain electrolyte balance. In case of extensive damage, the kidney's filtration capacity is impaired and cannot fulfill its functions. Fluvoxamine (FLV), an antidepressant agent, has antioxidant and anti-inflammatory effects.
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