Periodontal bone defects, primarily caused by periodontitis, are highly prevalent in clinical settings and manifest as bone fenestration, dehiscence, or attachment loss, presenting a significant challenge to oral health. In regenerative medicine, harnessing developmental principles for tissue repair offers promising therapeutic potential. Of particular interest is the condensation of progenitor cells, an essential event in organogenesis that has inspired clinically effective cell aggregation approaches in dental regeneration. However, the precise cellular coordination mechanisms during condensation and regeneration remain elusive. Here, taking the tooth as a model organ, we employed single-cell RNA sequencing to dissect the cellular composition and heterogeneity of human dental follicle and dental papilla, revealing a distinct Platelet-derived growth factor receptor alpha (PDGFRA) mesenchymal stem/stromal cell (MSC) population with remarkable odontogenic potential. Interestingly, a reciprocal paracrine interaction between PDGFRA⁺ dental follicle stem cells (DFSCs) and CD31⁺ Endomucin⁺ endothelial cells (ECs) was mediated by Vascular endothelial growth factor A (VEGFA) and Platelet-derived growth factor subunit BB (PDGFBB). This crosstalk not only maintains the functionality of PDGFRA⁺ DFSCs but also drives specialized angiogenesis. In vivo periodontal bone regeneration experiments further reveal that communication between PDGFRA⁺ DFSC aggregates and recipient ECs is essential for effective angiogenic-osteogenic coupling and rapid tissue repair. Collectively, our results unravel the importance of MSC-EC crosstalk mediated by the VEGFA and PDGFBB-PDGFRA reciprocal signaling in orchestrating angiogenesis and osteogenesis. These findings not only establish a framework for deciphering and promoting periodontal bone regeneration in potential clinical applications but also offer insights for future therapeutic strategies in dental or broader regenerative medicine.
Receptor, Platelet-Derived Growth Factor alpha/metabolism* ; Humans ; Neovascularization, Physiologic/physiology* ; Dental Sac/cytology* ; Single-Cell Analysis ; Transcriptome ; Mesenchymal Stem Cells/metabolism* ; Bone Regeneration ; Animals ; Dental Papilla/cytology* ; Periodontium/physiology* ; Stem Cells/metabolism* ; Regeneration ; Angiogenesis

Objective To explore the clinical values of voxel-based morphometry(VBM)analysis in magnetic resonance imaging(MRI)for detecting secondary damage to the distant thalamus and substantia nigra in patients with cerebral infarction.Methods A total of nineteen patients with first-time unilateral middle cerebral artery(MCA)ischemic stroke were prospectively recruited.Three-dimensional whole-brain MRI scans were performed at 1 week,1 month,and 3 months after onset.VBM analysis was used to analyze changes in the thalamus and substantia nigra volumes.Results VBM analysis revealed that compared to ipsilateral thalamic volume at 1 week after onset,ipsilateral thalamic volume was significantly reduced at 1 month or 3 months after onset(reduced by 637 mm3 and 1488 mm3,respectively;P<0.01),with the atrophy primarily located in the dorsomedial nucleus of the thalamus.Similarly,compared to ipsilateral substantia nigra volume at 1 week after onset,the ipsilateral substantia nigra volume was significantly reduced at 1 month or 3 months after onset(reduced by 64 mm3 and 76 mm3,respectively;P<0.05).Conclusions VBM technology can be used to evaluate the ipsilateral thalamic and substantia nigra volume reduction in patients with cerebral infarction in the MCA supply area at 1-3 months after stroke,and to detect secondary damage.

The case-based teaching was inserted in the lecture-based teaching in clinical microbiol-ogy. The teachers conducted the case-based teaching through proper selection of cases, leading students to discuss and analyze cases. The students explored and reported from the cases independently. Finally, the teachers summarized and evaluated from the case-based teaching. The combination of case-based teaching and lecture-based study stimulated the students' interest in learning and motivation, consolidated their theoretical knowledge, cultivated their abilities of self-learning and clinical idea, and made the correlation between the theory and the clinical practice closely. These methods improved the teaching quality of clinical microbiology.

The incidence of stroke increases year by year.It seriously affects the quality of life in patients.The pathogenesis of stroke is related to a variety of factors,involving genetic polymorphisms,biochemical mechanisms,and inflammatory effect.Among them,vascular endothelial growth factor (VEGF) has become one of the hotspots of research on the pathogenesis of stroke in recent years.This article reviews the correlation between VEGF gene polymorphism and stroke.

After ischemic stroke, secondary damages such as neuron loss, gliosis, and axonal degeneration occur in the nonischemic remote brain regions that have synaptic connections with the primary infarction site.These secondary damages in the remote brain regions may affect the recovery of neurological function.Several advanced neuroimaging techniques have been used to detect these secondary damages.This article reviews the research progress in this field.