Rentgenová výpočetní mikrotomografie (mikroCT) představuje moderní zobrazovací technologii s vysokým rozlišením umožňující detailní analýzu zobrazovaného vzorku. Nabízí jedinečný pohled na trojrozměrnou architekturu díky rozlišení na pomezí makroskopického a histologického zobrazení. V oblasti anatomické patologie mikroCT nachází uplatnění zejména při morfometrické analýze nádorů, hodnocení resekčních okrajů chirurgických vzorků či detekci metastáz v lymfatických uzlinách. Kombinace mikroCT s tradičními histopatologickými technikami a s využitím digitální 3D rekonstrukce otevírá nové možnosti při analýze komplexních patologických procesů. Přestože je tato metoda zatím převážně využívána ve výzkumu, její klinický potenciál je značný. Mezi hlavní přednosti patří neinvazivní zobrazení a možnost integrace s digitální patologií a nástroji umělé inteligence. Hlavními limitacemi v současné době zůstávají potřeba kontrastování vzorků, monochromatická povaha obrazu a vysoká radiační zátěž. Pokrok v technologickém vývoji však může tyto překážky překonat a umožnit širší využití mikroCT v rutinní klinické diagnostice. Tento článek představuje technologii mikroCT a její diagnostický potenciál v patologii, přibližuje její aplikace, výhody a omezení, a nabízí vhled do budoucí perspektivy jejího využití.
X-ray microtomography (microCT) represents a modern high-resolution imaging technology enabling detailed analysis of the tissue. It offers a unique perspective on three-dimensional architecture, bridging the gap between macroscopic and histological imaging. In anatomical pathology, microCT is particularly utilized for morphometric tumor analysis, evaluation of surgical specimen resection margins, and detection of metastases in lymph nodes. The combination of microCT with traditional histopathological techniques, and with digital 3D reconstructions, opens new avenues for analyzing complex pathological processes. Although this method is currently used in research, its clinical potential is significant. Key advantages include non-invasive imaging and the ability to be integrated with digital pathology and artificial intelligence tools. Current limitations include the need for sample contrast enhancement, the monochromatic nature of the images, and high radiation exposure. Advances in technological development, however, may overcome these barriers and enable the broader adoption of microCT in routine clinical diagnostics. This article explores the diagnostic potential of microCT in pathology, highlighting its applications, advantages, and limitations, while offering insights into current capabilities and future perspectives of this technology.
The chondrocranium provides the key initial support for the fetal brain, jaws and cranial sensory organs in all vertebrates. The patterns of shaping and growth of the chondrocranium set up species-specific development of the entire craniofacial complex. The 3D development of chondrocranium have been studied primarily in animal model organisms, such as mice or zebrafish. In comparison, very little is known about the full 3D human chondrocranium, except from drawings made by anatomists many decades ago. The knowledge of human-specific aspects of chondrocranial development are essential for understanding congenital craniofacial defects and human evolution. Here advanced microCT scanning was used that includes contrast enhancement to generate the first 3D atlas of the human fetal chondrocranium during the middle trimester (13 to 19 weeks). In addition, since cartilage and bone are both visible with the techniques used, the endochondral ossification of cranial base was mapped since this region is so critical for brain and jaw growth. The human 3D models are published as a scientific resource for human development.
- MeSH
- Cartilage diagnostic imaging embryology MeSH
- Skull diagnostic imaging embryology MeSH
- Humans MeSH
- Fetus diagnostic imaging MeSH
- X-Ray Microtomography MeSH
- Pregnancy MeSH
- Imaging, Three-Dimensional * MeSH
- Check Tag
- Humans MeSH
- Pregnancy MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Dataset MeSH
The development of craniofacial skeletal structures is fascinatingly complex and elucidation of the underlying mechanisms will not only provide novel scientific insights, but also help develop more effective clinical approaches to the treatment and/or prevention of the numerous congenital craniofacial malformations. To this end, we performed a genome-wide analysis of RNA transcription from non-coding regulatory elements by CAGE-sequencing of the facial mesenchyme of human embryos and cross-checked the active enhancers thus identified against genes, identified by GWAS for the normal range human facial appearance. Among the identified active cis-enhancers, several belonged to the components of the PI3/AKT/mTORC1/autophagy pathway. To assess the functional role of this pathway, we manipulated it both genetically and pharmacologically in mice and zebrafish. These experiments revealed that mTORC1 signaling modulates craniofacial shaping at the stage of skeletal mesenchymal condensations, with subsequent fine-tuning during clonal intercalation. This ability of mTORC1 pathway to modulate facial shaping, along with its evolutionary conservation and ability to sense external stimuli, in particular dietary amino acids, indicate that the mTORC1 pathway may play a role in facial phenotypic plasticity. Indeed, the level of protein in the diet of pregnant female mice influenced the activity of mTORC1 in fetal craniofacial structures and altered the size of skeletogenic clones, thus exerting an impact on the local geometry and craniofacial shaping. Overall, our findings indicate that the mTORC1 signaling pathway is involved in the effect of environmental conditions on the shaping of craniofacial structures.
The formation of hematopoietic cells relies on the chromatin remodeling activities of ISWI ATPase SMARCA5 (SNF2H) and its complexes. The Smarca5 null and conditional alleles have been used to study its functions in embryonic and organ development in mice. These mouse model phenotypes vary from embryonic lethality of constitutive knockout to less severe phenotypes observed in tissue-specific Smarca5 deletions, e.g., in the hematopoietic system. Here we show that, in a gene dosage-dependent manner, the hypomorphic allele of SMARCA5 (S5tg) can rescue not only the developmental arrest in hematopoiesis in the hCD2iCre model but also the lethal phenotypes associated with constitutive Smarca5 deletion or Vav1iCre-driven conditional knockout in hematopoietic progenitor cells. Interestingly, the latter model also provided evidence for the role of SMARCA5 expression level in hematopoietic stem cells, as the Vav1iCre S5tg animals accumulate stem and progenitor cells. Furthermore, their hematopoietic stem cells exhibited impaired lymphoid lineage entry and differentiation. This observation contrasts with the myeloid lineage which is developing without significant disturbances. Our findings indicate that animals with low expression of SMARCA5 exhibit normal embryonic development with altered lymphoid entry within the hematopoietic stem cell compartment.
- MeSH
- Adenosine Triphosphatases metabolism MeSH
- Cell Differentiation genetics MeSH
- Hematopoietic Stem Cells * metabolism MeSH
- Hematopoiesis * genetics MeSH
- Mice MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Primary cilia are cellular surface projections enriched in receptors and signaling molecules, acting as signaling hubs that respond to stimuli. Malfunctions in primary cilia have been linked to human diseases, including retinopathies and ocular defects. Here, we focus on TMEM107, a protein localized to the transition zone of primary cilia. TMEM107 mutations were found in patients with Joubert and Meckel-Gruber syndromes. A mouse model lacking Tmem107 exhibited eye defects such as anophthalmia and microphthalmia, affecting retina differentiation. Tmem107 expression during prenatal mouse development correlated with phenotype occurrence, with enhanced expression in differentiating retina and optic stalk. TMEM107 deficiency in retinal organoids resulted in the loss of primary cilia, down-regulation of retina-specific genes, and cyst formation. Knocking out TMEM107 in human ARPE-19 cells prevented primary cilia formation and impaired response to Smoothened agonist treatment because of ectopic activation of the SHH pathway. Our data suggest TMEM107 plays a crucial role in early vertebrate eye development and ciliogenesis in the differentiating retina.
- MeSH
- Humans MeSH
- Membrane Proteins genetics metabolism MeSH
- Mice MeSH
- Polycystic Kidney Diseases * genetics MeSH
- Ciliary Motility Disorders * genetics metabolism MeSH
- Retina metabolism MeSH
- Retinitis Pigmentosa * metabolism MeSH
- Pregnancy MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Mice MeSH
- Pregnancy MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Mineralized tissues, such as bones or teeth, are essential structures of all vertebrates. They enable rapid movement, protection, and food processing, in addition to providing physiological functions. Although the development, regeneration, and pathogenesis of teeth and bones have been intensely studied, there is currently no tool to accurately follow the dynamics of growth and healing of these vital tissues in space and time. Here, we present the BEE-ST (Bones and tEEth Spatio-Temporal growth monitoring) approach, which allows precise quantification of development, regeneration, remodeling, and healing in any type of calcified tissue across different species. Using mouse teeth as model the turnover rate of continuously growing incisors was quantified, and role of hard/soft diet on molar root growth was shown. Furthermore, the dynamics of bones and teeth growth in lizards, frogs, birds, and zebrafish was uncovered. This approach represents an effective, highly reproducible, and versatile tool that opens up diverse possibilities in developmental biology, bone and tooth healing, tissue engineering, and disease modeling.
- MeSH
- Zebrafish * MeSH
- Bone and Bones MeSH
- Mice MeSH
- Bone Development MeSH
- Tooth Root MeSH
- Tooth * physiology MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
In this study we use comparative genomics to uncover a gene with uncharacterized function (1700011H14Rik/C14orf105/CCDC198), which we hereby name FAME (Factor Associated with Metabolism and Energy). We observe that FAME shows an unusually high evolutionary divergence in birds and mammals. Through the comparison of single nucleotide polymorphisms, we identify gene flow of FAME from Neandertals into modern humans. We conduct knockout experiments on animals and observe altered body weight and decreased energy expenditure in Fame knockout animals, corresponding to genome-wide association studies linking FAME with higher body mass index in humans. Gene expression and subcellular localization analyses reveal that FAME is a membrane-bound protein enriched in the kidneys. Although the gene knockout results in structurally normal kidneys, we detect higher albumin in urine and lowered ferritin in the blood. Through experimental validation, we confirm interactions between FAME and ferritin and show co-localization in vesicular and plasma membranes.
- MeSH
- Genome-Wide Association Study * MeSH
- Energy Metabolism * genetics MeSH
- Ferritins genetics MeSH
- Kidney MeSH
- Humans MeSH
- Neanderthals MeSH
- Body Weight MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Formation of oriented myofibrils is a key event in musculoskeletal development. However, the mechanisms that drive myocyte orientation and fusion to control muscle directionality in adults remain enigmatic. Here, we demonstrate that the developing skeleton instructs the directional outgrowth of skeletal muscle and other soft tissues during limb and facial morphogenesis in zebrafish and mouse. Time-lapse live imaging reveals that during early craniofacial development, myoblasts condense into round clusters corresponding to future muscle groups. These clusters undergo oriented stretch and alignment during embryonic growth. Genetic perturbation of cartilage patterning or size disrupts the directionality and number of myofibrils in vivo. Laser ablation of musculoskeletal attachment points reveals tension imposed by cartilage expansion on the forming myofibers. Application of continuous tension using artificial attachment points, or stretchable membrane substrates, is sufficient to drive polarization of myocyte populations in vitro. Overall, this work outlines a biomechanical guidance mechanism that is potentially useful for engineering functional skeletal muscle.
- MeSH
- Zebrafish * genetics MeSH
- Muscle, Skeletal * physiology MeSH
- Morphogenesis MeSH
- Myoblasts physiology MeSH
- Myofibrils physiology MeSH
- Mice MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Research Support, N.I.H., Extramural MeSH
Spontaneous bleeds are a leading cause of death in the pediatric JAG1-related liver disease Alagille syndrome (ALGS). We asked whether there are sex differences in bleeding events in patients, whether Jag1Ndr/Ndr mice display bleeds or vascular defects, and whether discovered vascular pathology can be confirmed in patients non-invasively. We performed a systematic review of patients with ALGS and vascular events following PRISMA guidelines, in the context of patient sex, and found significantly more girls than boys reported with spontaneous intracranial hemorrhage. We investigated vascular development, homeostasis, and bleeding in Jag1Ndr/Ndr mice, using retina as a model. Jag1Ndr/Ndr mice displayed sporadic brain bleeds, a thin skull, tortuous blood vessels, sparse arterial smooth muscle cell coverage in multiple organs, which could be aggravated by hypertension, and sex-specific venous defects. Importantly, we demonstrated that retinographs from patients display similar characteristics with significantly increased vascular tortuosity. In conclusion, there are clinically important sex differences in vascular disease in ALGS, and retinography allows non-invasive vascular analysis in patients. Finally, Jag1Ndr/Ndr mice represent a new model for vascular compromise in ALGS.
- MeSH
- Alagille Syndrome * complications MeSH
- Mice MeSH
- Sex Characteristics MeSH
- Retina MeSH
- Risk Factors MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Mice MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Systematic Review MeSH
