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Despite the great efforts of basic and clinical research on lung cancer (LC), the prevention and treatment of this type of cancer show still far from satisfactory indicators. The complex mechanisms of the LC biology are already recognized, but there is a significant gap in the knowledge about the interaction of key biomarkers in the etiology and progression of this disease. The present work is aimed at studying the relationship between the telomere length (TL) and frequencies of chromosomal aberrations (CA) and micronuclei (MN) in leukocytes of primary lung cancer patients. In 67 men with lung cancer and 77 control donors (men), the baseline frequencies of CA and MN were determined in blood leukocytes, and TL was also studied. As a result, a significant increase in TL was found in lung cancer patients compared with control donors (25.86 ± 2.13 versus 15.29 ± 1.22, respectively, p = 0.00001). In leukocytes of LC patients, a significant increase in the baseline level of structural aberrations of chromosomes, as well as micronuclei containing centromeres, was noted. Only in the sample of lung cancer patients were direct correlations of TL with the frequency of chromosomal type aberrations and with the frequency of paired fragments revealed. In the same sample, significant inverse correlations of TL with the frequency of binucleated leukocytes containing nuclear protrusions and with the frequency of cells entering apoptosis were recorded. The study first showed that an increase in TL in lung cancer patients is associated with structural chromosomal damages, but not with the incidence of aneuploidies. [ABSTRACT FROM AUTHOR]

The ultimate aim of fluorescence microscopy is to achieve high-resolution imaging of increasingly larger biological samples. Extended depth of field presents a potential solution to accelerate imaging of large samples when compression of information along the optical axis is not detrimental to the interpretation of images. We have implemented an extended depth of field (EDF) approach in a random illumination microscope (RIM). RIM uses multiple speckled illuminations and variance data processing to double the resolution. It is particularly adapted to the imaging of thick samples as it does not require the knowledge of illumination patterns. We demonstrate highly-resolved projective images of biological tissues and cells. Compared to a sequential scan of the imaged volume with conventional 2D-RIM, EDF-RIM allows an order of magnitude improvement in speed and light dose reduction, with comparable resolution. As the axial information is lost in an EDF modality, we propose a method to retrieve the sample topography for samples that are organized in cell sheets., (© 2024. The Author(s).)

Scanning fluorescence microscopes are now able to image large biological samples at high spatial and temporal resolution. This comes at the expense of an increased light dose which is detrimental to fluorophore stability and cell physiology. To highly reduce the light dose, we designed an adaptive scanning fluorescence microscope with a scanning scheme optimized for the unsupervised imaging of cell sheets, which underly the shape of many embryos and organs. The surface of the tissue is first delineated from the acquisition of a very small subset (~0.1%) of sample space, using a robust estimation strategy. Two alternative scanning strategies are then proposed to image the tissue with an improved photon budget, without loss in resolution. The first strategy consists in scanning only a thin shell around the estimated surface of interest, allowing high reduction of light dose when the tissue is curved. The second strategy applies when structures of interest lie at the cell periphery (e.g. adherens junctions). An iterative approach is then used to propagate scanning along cell contours. We demonstrate the benefit of our approach imaging live epithelia from Drosophila melanogaster. On the examples shown, both approaches yield more than a 20-fold reduction in light dose -and up to more than 80-fold- compared to a full scan of the volume. These smart-scanning strategies can be easily implemented on most scanning fluorescent imaging modality. The dramatic reduction in light exposure of the sample should allow prolonged imaging of the live processes under investigation., (© 2021. The Author(s).)