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PubMed2026

Phylogenetic position of the enigmatic starfish family Podosphaerasteridae (Asteroidea, Valvatida) with a morphological observation of the skeletal structure by micro-CT.

Background The genus Podosphaeraster comprises seven species, characterised by a distinctive spherical body, all currently known from the seabed at depths below approximately 70 m. Its peculiar morphology has made its phylogenetic placement a subject of ongoing debate. It was initially suggested to be placed in Sphaerasteridae, the same family as fossil species. However, subsequent detailed skeletal analyses of the fossil forms suggested that this similarity was likely due to convergent evolution. Recent molecular analyses have revealed that Valvatida, in which the genus is currently placed, is likely a large polyphyletic group, leaving its taxonomic position still unresolved. New information A detailed examination of the internal skeletal structure of Podosphaeraster toyoshiomaruae, collected from the seas around Japan, was conducted using micro-focus X-ray computed tomography. Concurrently, shotgun sequencing was performed to identify key molecular markers for recent asteroid phylogeny. Additionally, shotgun sequencing determined the complete mitochondrial genome. Despite conservative evolution amongst asteroidean mitochondrial genomes, a translocation of the COX2 gene was revealed, representing the first discovery of a major protein-coding gene translocation within Asteroidea. In the phylogenetic tree, P. toyoshiomaruae was positioned as the most basal lineage within Valvatida. However, the statistical support for this placement was low, potentially due to the long-branch attraction caused by the excessively rapid evolutionary rate. Images reconstructed by micro-CT confirmed the presence of calcified reinforcement in the mesentery and showed its detailed structure for the first time. The mesentery skeleton was found to connect to the V-plate and five pairs of plates, including three kinds of marginal plates. This suggests that the marginal plates of this species may not be homologous with those of other asteroids. Although varying degrees of marginal plate reduction are shared with the order Velatida, we consider this to be a case of convergent evolution. Our phylogenetic analysis indicates a close relationship between P. toyoshiomaruae and Poraniidae (and other Valvatida), all of which possess marginal plates differentiated to varying extents, the homology of which remains uncertain.

Asteroidea↗

PubMed1990

Evaluation of a microcomputed tomography system to study trabecular bone structure.

A new microcomputed tomography (micro-CT) system and thresholding procedure was evaluated as a tool for nondestructive analysis of trabecular bone. Images of 6-mm trabecular bone cubes acquired from the micro-CT system were compared with optical images of corresponding histologic sections to determine the accuracy of representation. The stereologic measures of bone volume fraction (PP) and trabecular plate density (PL) were used to quantify the comparisons. The results showed that the micro-CT measures of PP were not significantly different from those measured from histologic sections and therefore were very accurate. Measures of PL were different by approximately 14%, which translated into discrepancies in trabecular plate thicknesses of about 19 microns. This difference was significantly correlated to the microstructural characteristics of the specific specimen scanned. The precision of both measurements was excellent.

Bone and Bones↗

PubMed2025

Mechanism of action of curculigoside ameliorating osteoporosis: an analysis based on network pharmacology and experimental validation.

OBJECTIVE: This study aimed to predict and verify the mechanism of curculigoside in treating osteoporosis using network pharmacology, molecular docking technology, and micro-CT technology. METHODS: Herb databases were searched to identify and screen potential targets of curculigoside. The GeneCards platform was utilized to mine osteoporosis-related targets. Cytoscape 3.6.0 software was employed to construct a compound-target-disease network. A protein-protein interaction (PPI) network for curculigoside in osteoporosis treatment was established, and core targets were screened. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and GO biological process analyses were performed using the Metascape database. Finally, molecular docking and micro-CT were used to validate core targets relevant to osteoporosis. RESULTS: A total of 166 potential curculigoside targets and 4,313 osteoporosis-related targets were identified, with 91 common targets. Ten key targets, including matrix metalloproteinase (MMP)3, MMP9, interleukin (IL)-6, and caspase-3, were screened. KEGG pathway enrichment analysis indicated involvement in 10 pathways, such as the Rap1 signaling pathway and tumor necrosis factor (TNF) signaling pathway. Molecular docking results demonstrated strong binding affinity between curculigoside and the core targets. Micro-CT analysis revealed that curculigoside not only improved BMD, BV/TV, BS/BV, and Tb.Th but also reduced Tb.Sp in osteoporotic bone. CONCLUSIONS: Curculigoside is likely to treat osteoporosis through targets such as MMP3, MMP9, IL-6, and caspase-3, acting on signaling pathways including Rap1 and TNF. These results indicate that curculigoside exhibits multitarget and multipathway characteristics in osteoporosis treatment, providing a theoretical basis for further clinical investigation.

Osteoporosis↗

PubMed2026

Longitudinal In Vivo Imaging at Single-Lesion Resolution Identifies Allele-Associated Response and Resistance Dynamics in EGFR-Mutant Lung Cancer.

Acquired resistance to targeted therapies is inevitable in EGFR-mutant non-small cell lung cancer (NSCLC), yet the principles governing its emergence in vivo remain incompletely understood. In particular, how lesion-level response patterns vary across distinct EGFR allele contexts during therapy has not been systematically examined at single-lesion resolution. Here, we establish a longitudinal in vivo imaging platform enabling single-lesion resolution tracking of tumor behavior during therapy in genetically engineered mouse models representing clinically relevant EGFR alleles. Using high-resolution micro-computed tomography (micro-CT) and three-dimensional reconstruction, we monitor tumor growth, therapeutic response, and resistance during osimertinib treatment. EGFR genotype is associated with distinct patterns of tumor growth, response kinetics, and resistance timing. Therapeutic response is spatially heterogeneous, with coexisting lesions undergoing complete regression, persistence, or progression within the same lung. During treatment, spatially distinct lesion-level behaviors included persistent growth during therapy and initial regression followed by regrowth. These findings demonstrate the utility of longitudinal micro-CT imaging to investigate allele-associated differences in treatment response and resistance timing at single-lesion resolution in vivo.

Animals↗

PubMed2026

Development of the zebrafish foveal analogue: a quantitative atlas of high-acuity zone growth and retinal regionalisation.

The vertebrate retina contains specialised regions for high-acuity vision, exemplified by the human fovea and its zebrafish analogue, the high-acuity zone (HAZ). Despite the widespread use of zebrafish to model retinal disease, a stage-resolved quantitative reference describing normal eye, photoreceptor layer (PRL) and lens growth has been lacking. Here, we apply contrast-enhanced micro-computed tomography (micro-CT) to construct the first three-dimensional micro-CT normative atlas of wild-type zebrafish eye development across five larval stages [3, 5, 7, 10 and 18 days post-fertilisation (dpf)], mapping circumferential PRL thickness, eye and lens morphology, and compartment growth rates. Regional PRL thickening within the temporo-ventral region of the expected HAZ emerged by 5 dpf and was sustained by a localised redistribution of growth, persisting and extending towards the optic nerve through 18 dpf. The PRL, lens and eye grew through four phases, alternating between disproportionate PRL expansion and coordinated growth, while the eye remodelled from a nasal-dominant to a temporo-ventral-dominant form. This regional specialisation was protracted relative to gross ocular growth and could proceed independently of it, paralleling the extended postnatal maturation of the human fovea. This atlas provides a quantitative baseline for distinguishing disease-induced changes from normal variation, supporting zebrafish models of foveal hypoplasia and related disorders.

Animals↗

PubMed2026

Dental phenotypes associated with novel PHEX variants in X-linked hypophosphatemia.

OBJECTIVES: X-linked hypophosphatemia (XLH) is a genetic disorder related to bone, mainly due to the mutations in PHEX gene. Previous studies have reported that XLH patients had various tooth phenotypes. It is unclear whether there are any rules about these abnormal tooth phenotypes, especially in those XLH cases with PHEX mutations. The objectives of this study were to find the most representative dental characteristics of XLH and the possible phenotype-genotype correlation. DESIGN: Two unrelated patients with XLH underwent clinical, radiographic, biochemical, and genetic evaluation. Whole-exome sequencing and whole-genome sequencing were used to identify pathogenic variants. The ultrastructure of extracted teeth was analyzed using a stereomicroscope, micro-CT, and scanning electron microscopy. In addition, a PubMed search (up to January 2026) identified 22 articles involving 366 patients for descriptive phenotype comparison. RESULTS: Two novel PHEX variants were identified: a novel complex structural variant (NC_000023.11, g.22035649-22041668delins) and a novel heterozygous splice-site variant (NM_000444.6, c.850-1 G>A). Radiographic examination showed enlarged pulp chambers and irregular pulp morphology. Ultrastructural analysis revealed dentin defects, including globular dentin, irregular interglobular dentin, disrupted dentinal tubules, and exposed collagen fibrils. Literature-based analysis indicated prevalent clinical manifestations (pulp necrosis, tooth loss, periodontitis) and radiographic findings (enlarged pulp chamber, and prominent pulp horn). CONCLUSION: In these two patients, novel PHEX variants were associated with a recurrent dentin-pulp phenotype. Integrated clinical, radiographic, ultrastructural, and literature evidence supports dentin defects as a central component of the dental phenotype in XLH and underscores the importance of early dental assessment.

Humans↗

PubMed2026

Generation of a novel Slc7a9G105R mutant mouse identifies new biomarkers for cystinuria.

INTRODUCTION: Cystinuria is a rare inherited disease characterized by increased urinary cystine levels resulting in the formation of cystine stones in the urinary tract. Mutations in the genes encoding the cystine transporter complex, SLC3A1 and SLC7A9, are the primary drivers of the disease. Current mouse models used to study cystinuria rely on gene deficiency or spontaneous mutations in mice that do not accurately reflect the pathogenic mutations found in humans. METHODS: We generated a novel Slc7a9G105R knock-in mouse model in which glycine at position 105 is replaced by arginine, recapitulating the most common pathogenic mutation in human SLC7A9. Disease onset and progression were assessed using micro-CT imaging, fecal metagenomics, and urine and serum metabolomics and proteomics. RESULTS: Both male and female Slc7a9G105R mice developed a cystinuria phenotype by nine weeks of age, characterized by substantial cystine stone formation and increased urinary cystine, lysine, arginine, and ornithine. Slc7a9G105R mice displayed distinct serum and urinary metabolite profiles, mapped to dibasic amino acid pathways, and serum protein profiles, mapped to disease progression. Fecal metagenomics revealed that Slc7a9G105R mice had a heterogeneous microbiota with altered functional pathways, including increased L-cysteine biosynthesis. Antibiotic-induced depletion of the microbiota did not affect cystine stone burden but reduced urinary tract inflammation. Prophylactic or therapeutic dietary supplementation with alpha-lipoic acid reduced stone burden and inflammation, but it also caused urothelial damage. Untargeted metabolomics analysis following alpha-lipoic acid supplementation identified metabolites that can increase cystine solubility, reduce inflammation, and damage epithelial cells. Correlation analysis revealed novel serum metabolite biomarkers of stone burden, including 2-hydroxybutyric acid and 2-amino-2-thiazoline-4-carboxylic acid, which were also detected in human serum. CONCLUSIONS: Collectively, the Slc7a9G105R mutant mouse model offers a precise, rapid-onset, and translational platform for investigating cystinuria pathogenesis and evaluating potential therapeutic strategies.

SLC7A9↗

PubMed2026

Targeting USP22 reprograms the tumor microenvironment and sensitizes KRAS/p53-driven lung cancer to anti-PD-1 immunotherapy.

RATIONALE: Ubiquitin-specific peptidase 22 (USP22), a deubiquitinase and component of the "Death-from-Cancer" 11-gene signature, is overexpressed in multiple malignancies and linked to recurrence, therapy resistance, and poor prognosis. Its role in KRAS/p53-driven lung cancer and the response to immune checkpoint inhibitors (ICIs) remains poorly defined. Here, we investigated USP22 as a potential therapeutic target in KRAS/p53-driven lung cancer. METHODS: A conditional Usp22 knockout (Usp22-KO) was generated in the KRASG12D; p53-/- (KP) mouse model. Cancer progression was monitored by micro-computed tomography (micro-CT). Multiplex immunofluorescence (mIF), RNA sequencing, and spatial transcriptomics profiled cancer and tumor microenvironment (TME) changes. Responses to anti-PD-1/PD-L1 therapies were compared between KP and Usp22-KO KP (KPU-) lung cancers. RESULTS: USP22 was highly expressed in early-stage KRAS/p53-driven mouse lung cancers and strongly correlated with proliferation marker Ki67. Usp22 deletion suppressed cancer growth, prolonged survival, and promoted cancer differentiation. Spatial transcriptomics and mIF revealed reduced CD206+ M2 macrophages, myeloid-derived suppressor cells (MDSCs), TGF-β1, and angiogenesis, along with increased functional CD8+ T cells. Mechanistically, USP22 regulated gene expression and protein stability, reducing c-Myc, PD-L1, TGF-β1, and SPARC upon Usp22 loss. Compared with KP cancer, KPU- and SPARC-knockdown KP cancers showed reduced macrophage chemotaxis and impaired basal- and TGF-β1-induced M2 polarization of RAW264.7 cells, suggesting that TGF-β1 and SPARC downregulation partially contributes to decreased M2 macrophage infiltration in KPU- cancers. Notably, Usp22 loss enhanced the efficacy of anti-PD-L1 and anti-PD-1 therapies in orthotopic and subcutaneous KP lung cancer models, respectively. USP22 and SPARC expression were also strongly correlated in human lung cancers. CONCLUSIONS: USP22 promotes progression and immune evasion in KRAS/p53-driven lung cancer. Targeting USP22 reprograms the TME, suppresses oncogenic signaling, and sensitizes tumors to ICI, establishing USP22 as a promising therapeutic target.

Animals↗

PubMed2026

Vertical distribution of accessory canals in different tooth types: A systematic review and meta-analysis.

OBJECTIVE: To systematically analyze the vertical distribution of accessory canals and propose potential root-end resection levels in different tooth types. DATA: Proportional distribution of accessory canals (PD-AC) in 1 mm intervals, cumulative proportions within 2 mm and 3 mm (CP-AC0-2 and CP-AC0-3), mean distance from accessory foramen to root apex or main foramen (MD-AF), and prevalence of accessory canals in 2D cross-sections (PR-AC-2D). SOURCES: A systematic search of electronic databases was conducted through December 25, 2025. The review was registered in PROSPERO (CRD420251107855). STUDY SELECTION: Two reviewers independently performed study selection, data extraction, and risk of bias assessment using the AQUA tool. Nineteen studies were included for qualitative synthesis, of which eleven provided sufficient data for meta-analysis. A random-effects model was used, and subgroup analyses were stratified by tooth type, accessory canal type, and country. Within 0-1 mm, 1-2 mm, 2-3 mm, and 3-4 mm from the apex, 41.5%, 34.3%, 9.9%, and 4.4% of accessory canals were located, respectively. Molars had significantly higher proportions than anterior teeth both within 2 mm (90.0% vs. 72.4%) and 3 mm (96.9% vs. 87.5%). Of apical ramifications, 86.4% were within 2 mm. The pooled MD-AF was 1.472 mm. PR-AC-2D decreased from 29.3% at 1 mm to 1.3% at 5 mm. All studies presented moderate to high risk of bias. CONCLUSIONS: A 2 mm root-end resection level may be sufficient for molars, whereas anterior teeth may require a higher level. Further randomized controlled trials are needed. CLINICAL SIGNIFICANCE: A 2 mm resection may adequately expose or remove most accessory canals in molars, potentially preserving more root length while maintaining treatment efficacy. In anterior teeth, a traditional 3 mm resection remains advisable until further evidence becomes available.

Humans↗

PubMed2026

Volumetric bone marrow cellularity (VBMC) assessment from routinely processed trephines using three-dimensional x-ray histology and gaussian peak modelling.

Objective.Bone marrow cellularity is routinely estimated from a small number of two-dimensional histology sections, making assessment sensitive to section representativeness, processing artefacts and observer interpretation. Three-dimensional (3D) x-ray histology (XRH), using x-ray computed microtomography (µCT), enables non-destructive whole-block imaging of trephine biopsies. This study evaluated whether XRH combined with Gaussian peak modelling could provide a pragmatic whole-block volumetric bone marrow cellularity (VBMC) estimate from formalin-fixed paraffin-embedded (FFPE) trephine biopsy blocks.Approach.Six routinely processed FFPE bone marrow trephine blocks were imaged using µCT-based XRH at ∼15 µm spatial resolution. VBMC was defined as the red-marrow (RM) fraction of the marrow soft-tissue compartment, RM/(RM + intra-biopsy wax), with wax serving as the volumetric proxy for adipocyte/yellow marrow space. Whole-volume greyscale histograms were modelled using a three-peak Gaussian approach representing intra-biopsy wax, RM and demineralised trabecular matrix. Peak-height and area-under-the-curve metrics were compared with whole-volume 3D segmentation and clinical two-dimensional (2D) cellularity estimates.Main Results.Gaussian peak modelling successfully approximated the segmented tissue-phase distributions. The peak-height-derived VBMC metric showed the closest agreement with whole-volume 3D segmentation, with an average absolute percentage difference of 9.3%, compared with 18.6% for clinical expert 2D cellularity estimates. The area-under-the-curve metric followed similar trends but consistently overestimated VBMC. Clinical 2D cellularity broadly followed whole-biopsy trends but showed one discordant case not explained by slice-position sampling alone. XRH also enabled unrestricted virtual reslicing and visualisation of sectioning-associated artefacts prior to further microtomy.Significance.Pre-sectioning XRH combined with Gaussian peak modelling provides a rapid, segmentation-free route to volumetric cellularity estimation from intact clinical FFPE trephine blocks. The approach supports objective whole-biopsy assessment while remaining compatible with routine histopathology workflows, reflecting the expected limitations of section-based visual estimation despite its role as the current clinical standard. In the near term, it could provide a non-disruptive adjunct to conventional 2D cellularity reporting, pending larger validation studies.

Imaging, Three-Dimensional↗