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Biology subjects

Olivo, A.

Publications and source records attributed to Olivo, A..

3 recordsLinked to original sources

An imaging framework for nuclei-based three-dimensional cell quantification in intact tissue using phase-contrast X-ray CT

Objective. Quantitative analysis of cellular morphology and spatial organisation within intact tissue remains challenging, particularly when three-dimensional information must be preserved. This study investigates whether laboratory propagation-based phase-contrast X-ray computed tomography (CT) can support nuclei-based quantitative analysis in unstained tissue while retaining the surrounding tissue architecture. Approach. We propose a nuclei-based quantitative imaging workflow that combines laboratory propagation-based phase-contrast X-ray CT with volumetric segmentation. Intact unstained liver tissue was imaged at cellular resolution, then nuclei were segmented throughout the reconstructed volume and quantitative metrics describing the nuclear morphology and spatial organisation were extracted. The resulting measurements were evaluated in two non-overlapping volumes of interest and compared with histological reference data using thickness-matched virtual CT slices. Main results. The proposed workflow enabled visualisation and segmentation of individual nuclei throughout intact unstained liver tissue. Comparable nuclear morphology and spatial organisation metrics were obtained from two non-overlapping volumes of interest, indicating stable segmentation performance within the analysed specimen. Comparison with H&E histology demonstrated broad agreement in nuclear morphology. Significance. This work demonstrates the feasibility of nuclei-based quantitative analysis using laboratory phase-contrast X-ray CT in intact unstained tissue. The approach provides volumetric cellular information while preserving tissue architecture and may complement conventional histological assessment in applications requiring three- dimensional analysis. These findings highlight the potential of laboratory phase-contrast CT for quantitative tissue characterisation and spatial cellular analysis

bioengineering↗

Single cell-guided prenatal derivation of primary epithelial organoids from the human amniotic and tracheal fluids.

Despite advances in prenatal diagnosis, it is still difficult to predict severity and outcomes of many congenital malformations. New patient-specific prenatal disease modelling may optimise personalised prediction. We and others have described the presence of mesenchymal stem cells in amniotic fluid (AFSC) that can generate induced pluripotent stem cells (iPSCs). The lengthy reprogramming processes, however, limits the ability to define individual phenotypes or plan prenatal treatment. Therefore, it would be advantageous if fetal stem cells could be obtained during pregnancy and expanded without reprogramming. Using single cell analysis, we characterised the cellular identities in amniotic fluid (AF) and identified viable epithelial stem/progenitor cells of fetal intestinal, renal and pulmonary origin. With relevance for prenatal disease modelling, these cells could be cultured to form clonal epithelial organoids manifesting small intestine, kidney and lung identity. To confirm this, we derived lung organoids from AF and tracheal fluid (TF) cells of Congenital Diaphragmatic Hernia (CDH) fetuses and found that they show differences to non-CDH controls and can recapitulate some pathological features of the disease. Amniotic Fluid Organoids (AFO) allow investigation of fetal epithelial tissues at clinically relevant developmental stages and may enable the development of therapeutic tools tailored to the fetus, as well as to predicting the effects of such therapies.

cell biology↗

Invasive breast tumors are characterized by the presence of crystalline nanoparticles

The presence of calcifications on mammograms is a widely used diagnostic marker for breast cancer. While the clinicopathological analysis of breast tissue is well-developed, an in-depth characterisation of the properties of calcifications at the micro and nano scale remained elusive. In this work, we use nano-analytical methods to investigate the calcification present in healthy breast tissue, as well as in benign and malignant breast tumour tissue biopsies. While polycrystalline apatite with lower crystallinity can be found in all breast tissue samples, we show that magnesium-containing nano and micro spherical particles are found only in malignant invasive breast cancers. These particles concentration increases with cancer progression. The discovery of these spherical particles provides new insights into the characteristics of breast calcification associated with malignant tumours and opens new research pathways to a better understanding of breast tumours and their microenvironment in general.

cancer biology↗