Functional dissection of parabrachial substrates in processing nociceptive information.

Painful stimuli elicit first-line reflexive defensive reactions and, in many cases, also evoke second-line recuperative behaviors, the latter of which reflects the sensing of tissue damage and the alleviation of suffering. The lateral parabrachial nucleus (lPBN), composed of external- (elPBN), dorsal- (dlPBN), and central/superior-subnuclei (jointly referred to as slPBN), receives sensory inputs from spinal projection neurons and plays important roles in processing affective information from external threats and body integrity disruption. However, the organizational rules of lPBN neurons that provoke diverse behaviors in response to different painful stimuli from cutaneous and deep tissues remain unclear. In this study, we used region-specific neuronal depletion or silencing approaches combined with a battery of behavioral assays to show that slPBN neurons expressing substance P receptor ( NK1R) (lPBN NK1R) are crucial for driving pain-associated self-care behaviors evoked by sustained noxious thermal and mechanical stimuli applied to skin or bone/muscle, while elPBN neurons are dispensable for driving such reactions. Notably, lPBN NK1R neurons are specifically required for forming sustained somatic pain-induced negative teaching signals and aversive memory but are not necessary for fear-learning or escape behaviors elicited by external threats. Lastly, both lPBN NK1R and elPBN neurons contribute to chemical irritant-induced nocifensive reactions. Our results reveal the functional organization of parabrachial substrates that drive distinct behavioral outcomes in response to sustained pain versus external danger under physiological conditions.

Ultrasound-Responsive Aligned Piezoelectric Nanofibers Derived Hydrogel Conduits for Peripheral Nerve Regeneration.

Nerve guidance conduits (NGCs) are considered as promising treatment strategy and frontier trend for peripheral nerve regeneration, while their therapeutic outcomes are limited by the lack of controllable drug delivery and available physicochemical cues. Herein, novel aligned piezoelectric nanofibers derived hydrogel NGCs with ultrasound (US)-triggered electrical stimulation (ES) and controllable drug release for repairing peripheral nerve injury are proposed. The inner layer of the NGCs is the barium titanate piezoelectric nanoparticles (BTNPs)-doped polyvinylidene fluoride-trifluoroethylene [BTNPs/P(VDF-TrFE)] electrospinning nanofibers with improved piezoelectricity and aligned orientation. The outer side of the NGCs is the thermoresponsive poly(N-isopropylacrylamide) hybrid hydrogel with bioactive drug encapsulation. Such NGCs can not only induce neuronal-oriented extension and promote neurite outgrowth with US-triggered wireless ES, but also realize the controllable nerve growth factor release with the hydrogel shrinkage under US-triggered heating. Thus, the NGC can positively accelerate the functional recovery and nerve axonal regeneration of rat models with long sciatic nerve defects. It is believed that the proposed US-responsive aligned piezoelectric nanofibers derived hydrogel NGCs will find important applications in clinic neural tissue engineering.

Calcified apoptotic vesicles from PROCR+ fibroblasts initiate heterotopic ossification.

Heterotopic ossification (HO) comprises the abnormal formation of ectopic bone in extraskeletal soft tissue. The factors that initiate HO remain elusive. Herein, we found that calcified apoptotic vesicles (apoVs) led to increased calcification and stiffness of tendon extracellular matrix (ECM), which initiated M2 macrophage polarization and HO progression. Specifically, single-cell transcriptome analyses of different stages of HO revealed that calcified apoVs were primarily secreted by a PROCR+ fibroblast population. In addition, calcified apoVs enriched calcium by annexin channels, absorbed to collagen I via electrostatic interaction, and aggregated to produce calcifying nodules in the ECM, leading to tendon calcification and stiffening. More importantly, apoV-releasing inhibition or macrophage deletion both successfully reversed HO development. Thus, we are the first to identify calcified apoVs from PROCR+ fibroblasts as the initiating factor of HO, and might serve as the therapeutic target for inhibiting pathological calcification.

Limited exposure of captive Australian marsupials to plastics.

The global concern regarding the ubiquitous presence of plastics in the environment has led to intensified research on the impact of these materials on wildlife. In the Australian context, marsupials represent a unique and diverse group of mammals, yet little is known about their exposures to plastics. This study aimed to assess the contamination levels of seven common plastics (i.e., polystyrene (PS), polycarbonate (PC), poly-(methyl methacrylate) (PMMA), polypropylene (PP), polyethylene terephthalate (PET), polyethylene (PE), and polyvinyl chloride (PVC)) in both the diet and faeces of kangaroos, wallabies and koalas sampled from a sanctuary in Northeastern Australia. Quantitative analysis was performed by pressurized liquid extraction followed by double-shot microfurnace pyrolysis coupled to gas chromatography mass spectrometry. Interestingly, the analysis of the food and faeces samples revealed the absence of detectable plastic particles; with this preliminary finding suggesting a relatively limited exposure of captive Australian marsupials to plastics. This study contributes valuable insights into the current state of plastic contamination in Australian marsupials, shedding light on the limited exposures and potential risks, and highlighting the need for continued monitoring and conservation efforts. The results underscore the importance of proactive measures to mitigate plastic pollution and protect vulnerable wildlife populations in Australia's unique ecosystems.

Bacteria-mediated resistance of neutrophil extracellular traps to enzymatic degradation drives the formation of dental calculi.

Dental calculi can cause gingival bleeding and periodontitis, yet the mechanism underlying the formation of such mineral build-ups, and in particular the role of the local microenvironment, are unclear. Here we show that the formation of dental calculi involves bacteria in local mature biofilms converting the DNA in neutrophil extracellular traps (NETs) from being degradable by the enzyme DNase I to being degradation resistant, promoting the nucleation and growth of apatite. DNase I inhibited NET-induced mineralization in vitro and ex vivo, yet plasma DNases were ineffective at inhibiting ectopic mineralization in the oral cavity in rodents. The topical application of the DNA-intercalating agent chloroquine in rodents fed with a dental calculogenic diet reverted NET DNA to its degradable form, inhibiting the formation of calculi. Our findings may motivate therapeutic strategies for the reduction of the prevalence of the deposition of bacteria-driven calculi in the oral cavity.

METTL14-mediated m6A epitranscriptomic modification contributes to chemotherapy-induced neuropathic pain by stabilizing GluN2A expression via IGF2BP2.

Epigenetics is a biological process that modifies and regulates gene expression, affects neuronal function, and contributes to pain. However, the mechanism by which epigenetics facilitates and maintains chronic pain is poorly understood. We aimed to determine whether N6-methyladenosine (m6A) specifically modified by methyltransferase-like 14 (METTL14) alters neuronal activity and governs pain by sensitizing the GluN2A subunit of the N-methyl-d-aspartate receptor (NMDAR) in the dorsal root ganglion (DRG) neurons in a model of chemotherapy-induced neuropathic pain (CINP). Using dot blotting, immunofluorescence, gain/loss-of-function, and behavioral assays, we found that m6A levels were upregulated in L4-L6 DRG neurons in CINP in a DBP/METTL14-dependent manner, which was also confirmed in human DRGs. Blocking METTL14 reduced m6A methylation and attenuated pain hypersensitivity. Mechanistically, METTL14-mediated m6A modification facilitated the synaptic plasticity of DRG neurons by enhancing the GluN2A subunit of NMDAR, and inhibiting METTL14 blocked this effect. In contrast, overexpression of METTL14 upregulated m6A modifications, enhanced presynaptic NMDAR activity in DRG neurons, and facilitated pain sensation. Our findings reveal a previously unrecognized mechanism of METTL14-mediated m6A modification in DRG neurons to maintain neuropathic pain. Targeting these molecules may provide a new strategy for pain treatment.

Interorgan communication in neurogenic heterotopic ossification: the role of brain-derived extracellular vesicles.

Brain-derived extracellular vesicles participate in interorgan communication after traumatic brain injury by transporting pathogens to initiate secondary injury. Inflammasome-related proteins encapsulated in brain-derived extracellular vesicles can cross the blood‒brain barrier to reach distal tissues. These proteins initiate inflammatory dysfunction, such as neurogenic heterotopic ossification. This recurrent condition is highly debilitating to patients because of its relatively unknown pathogenesis and the lack of effective prophylactic intervention strategies. Accordingly, a rat model of neurogenic heterotopic ossification induced by combined traumatic brain injury and achillotenotomy was developed to address these two issues. Histological examination of the injured tendon revealed the coexistence of ectopic calcification and fibroblast pyroptosis. The relationships among brain-derived extracellular vesicles, fibroblast pyroptosis and ectopic calcification were further investigated in vitro and in vivo. Intravenous injection of the pyroptosis inhibitor Ac-YVAD-cmk reversed the development of neurogenic heterotopic ossification in vivo. The present work highlights the role of brain-derived extracellular vesicles in the pathogenesis of neurogenic heterotopic ossification and offers a potential strategy for preventing neurogenic heterotopic ossification after traumatic brain injury. Brain-derived extracellular vesicles (BEVs) are released after traumatic brain injury. These BEVs contain pathogens and participate in interorgan communication to initiate secondary injury in distal tissues. After achillotenotomy, the phagocytosis of BEVs by fibroblasts induces pyroptosis, which is a highly inflammatory form of lytic programmed cell death, in the injured tendon. Fibroblast pyroptosis leads to an increase in calcium and phosphorus concentrations and creates a microenvironment that promotes osteogenesis. Intravenous injection of the pyroptosis inhibitor Ac-YVAD-cmk suppressed fibroblast pyroptosis and effectively prevented the onset of heterotopic ossification after neuronal injury. The use of a pyroptosis inhibitor represents a potential strategy for the treatment of neurogenic heterotopic ossification.

Lysosomal destabilization: A missing link between pathological calcification and osteoarthritis.

Calcification of cartilage by hydroxyapatite is a hallmark of osteoarthritis and its deposition strongly correlates with the severity of osteoarthritis. However, no effective strategies are available to date on the prevention of hydroxyapatite deposition within the osteoarthritic cartilage and its role in the pathogenesis of this degenerative condition is still controversial. Therefore, the present work aims at uncovering the pathogenic mechanism of intra-cartilaginous hydroxyapatite in osteoarthritis and developing feasible strategies to counter its detrimental effects. With the use of in vitro and in vivo models of osteoarthritis, hydroxyapatite crystallites deposited in the cartilage are found to be phagocytized by resident chondrocytes and processed by the lysosomes of those cells. This results in lysosomal membrane permeabilization (LMP) and release of cathepsin B (CTSB) into the cytosol. The cytosolic CTSB, in turn, activates NOD-like receptor protein-3 (NLRP3) inflammasomes and subsequently instigates chondrocyte pyroptosis. Inhibition of LMP and CTSB in vivo are effective in managing the progression of osteoarthritis. The present work provides a conceptual therapeutic solution for the prevention of osteoarthritis via alleviation of lysosomal destabilization.

Fibrocyte: A missing piece in the pathogenesis of fibrous epulis.

OBJECTIVES: To explore the role of fibrocytes in the recurrence and calcification of fibrous epulides. METHODS: Different subtypes of fibrous epulides and normal gingival tissue specimens were first collected for histological and immunofluorescence analyses to see if fibrocytes were present and whether they differentiated into myofibroblasts and osteoblasts upon stimulated by transforming growth factor-ß1 (TGF-ß1). Electron microscopy and elemental analysis were used to characterize the extracellular microenvironment in different subtypes of fibrous epulides. Human peripheral blood mononuclear cells (PBMCs) were subsequently isolated from in vitro models to mimic the microenvironment in fibrous epulides to identify whether TGF-ß1 as well as the calcium and phosphorus ion concentration in the extracellular matrix (ECM) of a fibrous epulis trigger fibrocyte differentiation. RESULTS: Fibrous epulides contain fibrocytes that accumulate in the local inflammatory environment and have the ability to differentiate into myofibroblasts or osteoblasts. TGF-ß1 promotes fibrocytes differentiation into myofibroblasts in a concentration-dependent manner, while TGF-ß1 stimulates the fibrocytes to differentiate into osteoblasts when combined with a high calcium and phosphorus environment. CONCLUSIONS: Our study revealed fibrocytes play an important role in the fibrogenesis and osteogenesis in fibrous epulis, and might serve as a therapeutic target for the inhibition of recurrence of fibrous epulides.

Ac4C Enhances the Translation Efficiency of Vegfa mRNA and Mediates Central Sensitization in Spinal Dorsal Horn in Neuropathic Pain.

N4-Acetylcytidine (ac4C), a highly conserved post-transcriptional machinery with extensive existence for RNA modification, plays versatile roles in various cellular processes and functions. However, the molecular mechanism by which ac4C modification mediates neuropathic pain remains elusive. Here, it is found that the enhanced ac4C modification promotes the recruitment of polysome in Vegfa mRNA and strengthens the translation efficiency following SNI. Nerve injury increases the expression of NAT10 and the interaction between NAT10 and Vegfa mRNA in the dorsal horn neurons, and the gain and loss of NAT10 function further confirm that NAT10 is involved in the ac4C modification in Vegfa mRNA and pain behavior. Moreover, the ac4C-mediated VEGFA upregulation contributes to the central sensitivity and neuropathic pain induced by SNI or AAV-hSyn-NAT10. Finally, SNI promotes the binding of HNRNPK in Vegfa mRNA and subsequently recruits the NAT10. The enhanced interaction between HNRNPK and NAT10 contributes to the ac4C modification of Vegfa mRNA and neuropathic pain. These findings suggest that the enhanced interaction between HNRNPK and Vegfa mRNA upregulates the ac4C level by recruiting NAT10 and contributes to the central sensitivity and neuropathic pain following SNI. Blocking this cascade may be a novel therapeutic approach in patients with neuropathic pain.

Identifying circRNA-miRNA-mRNA Regulatory Networks in Chemotherapy-Induced Peripheral Neuropathy.

Chemotherapy-induced peripheral neuropathy (CIPN) is a frequent and severe side effect of first-line chemotherapeutic agents. The association between circular RNAs (circRNAs) and CIPN remains unclear. In this study, CIPN models were constructed with Taxol, while 134 differentially expressed circRNAs, 353 differentially expressed long non-coding RNAs, and 86 differentially expressed messenger RNAs (mRNAs) were identified utilizing RNA sequencing. CircRNA-targeted microRNAs (miRNAs) were predicted using miRanda, and miRNA-targeted mRNAs were predicted using TargetScan and miRDB. The intersection of sequencing and mRNA prediction results was selected to establish the circRNA-miRNA-mRNA networks, which include 15 circRNAs, 18 miRNAs, and 11 mRNAs. Functional enrichment pathway analyses and immune infiltration analyses revealed that differentially expressed mRNAs were enriched in the immune system, especially in T cells, monocytes, and macrophages. Cdh1, Satb2, Fas, P2ry2, and Zfhx2 were further identified as hub genes and validated by RT-qPCR, correlating with macrophages, plasmacytoid dendritic cells, and central memory CD4 T cells in CIPN. Additionally, we predicted the associated diseases, 36 potential transcription factors (TFs), and 30 putative drugs for hub genes using the DisGeNET, TRRUST, and DGIdb databases, respectively. Our results indicated the crucial role of circRNAs, and the immune microenvironment played in CIPN, providing novel insights for further research.

POU2F1/DNMT3a Pathway Participates in Neuropathic Pain by Hypermethylation-Mediated LRFN4 Downregulation Following Oxaliplatin Treatment.

Evidence demonstrates that DNA methylation is associated with the occurrence and development of various neurological diseases. However, the potential target genes undergoing DNA methylation, as well as their involvement in the chemotherapy drug oxaliplatin-induced neuropathic pain, are still unclear. Here, Lrfn4, which showed hypermethylation in the promoter regions, was screened from the SRA methylation database (PRJNA587622) following oxaliplatin treatment. MeDIP and qPCR assays identified that oxaliplatin treatment increased the methylation in Lrfn4 promoter region and decreased the expression of LRFN4 in the spinal dorsal horn. The assays with gain and loss of LRFN4 function demonstrated that LRFN4 downregulation in spinal dorsal horn contributed to the oxaliplatin-induced mechanical allodynia and cold hyperalgesia. Moreover, oxaliplatin treatment increased the DNA methyltransferases DNMT3a expression and the interaction between DNMT3a and Lrfn4 promoter, while inhibition of DNMT3a prevented the downregulation of LRFN4a induced by oxaliplatin. We also observed that the transcriptional factor POU2F1 can bind to the predicted sites in DNMT3a promoter region, oxaliplatin treatment upregulated the expression of transcriptional factor POU2F1 in dorsal horn neurons. Intrathecal injection of POU2F1 siRNA prevented the DNMT3a upregulation and the LRFN4 downregulation induced by oxaliplatin. Additionally, intrathecal injection of DNMT3a siRNA or POU2F1 siRNA alleviated the mechanical allodynia induced by oxaliplatin. These findings suggested that transcription factor POU2F1 upregulated the expression of DNMT3a, which subsequently decreased LRFN4 expression through hypermethylation modification in spinal dorsal horn, thereby mediating neuropathic pain following oxaliplatin treatment.

Multi-Target Neural Differentiation (MTND) Therapeutic Cocktail to Suppress Brain Tumor.

Brain tumors have been proved challenging to treat. Here we established a Multi-Target Neural Differentiation (MTND) therapeutic cocktail to achieve effective and safe treatment of brain malignancies by targeting the important hallmarks in brain cancers: poor cell differentiation and compromised cell cycle. In-vitro and in-vivo experiments confirmed the significant therapeutic effect of our MTND therapy. Significantly improved therapeutic effects over current first-line chemo-drugs have been identified in clinical cells, with great inhibition of the growth and migration of tumor cells. Further in-vivo experiments confirmed that sustained MTND treatment showed a 73% reduction of the tumor area. MTND also induced strong expression of phenotypes associated with cell cycle exit/arrest and rapid neural reprograming from clinical glioma cells to glutamatergic and GABAergic expressing cells, which are two key neuronal types involved in many human brain functions, including learning and memory. Collectively, MTND induced multi-targeted genotypic expression changes to achieve direct neural conversion of glioma cells and controlled the cell cycle/tumorigenesis development, helping control tumor cells' malignant proliferation and making it possible to treat brain malignant tumors effectively and safely. These encouraging results open avenues to developing new therapies for brain malignancies beyond cytotoxic agents, providing more effective medication recommendations with reduced toxicity.

Brain-specific Pd1 deficiency leads to cortical neurogenesis defects and depressive-like behaviors in mice.

Embryonic neurogenesis is tightly regulated by multiple factors to ensure the precise development of the cortex. Deficiency in neurogenesis may result in behavioral abnormalities. Pd1 is a well-known inhibitory immune molecule, but its function in brain development remains unknown. Here, we find brain specific deletion of Pd1 results in abnormal cortical neurogenesis, including enhanced proliferation of neural progenitors and reduced neuronal differentiation. In addition, neurons in Pd1 knockout mice exhibit abnormal morphology, both the total length and the number of primary dendrites were reduced. Moreover, Pd1cKO mice exhibit depressive-like behaviors, including immobility, despair, and anhedonia. Mechanistically, Pd1 regulates embryonic neurogenesis by targeting Pax3 through the ß-catenin signaling pathway. The constitutive expression of Pax3 partly rescues the deficiency of neurogenesis in the Pd1 deleted embryonic brain. Besides, the administration of ß-catenin inhibitor, XAV939, not only rescues abnormal brain development but also ameliorates depressive-like behaviors in Pd1cKO mice. Simultaneously, Pd1 plays a similar role in human neural progenitor cells (hNPCs) proliferation and differentiation. Taken together, our findings reveal the critical role and regulatory mechanism of Pd1 in embryonic neurogenesis and behavioral modulation, which could contribute to understanding immune molecules in brain development.

Effect of Extracellular Ribonucleic Acids on Neurovascularization in Osteoarthritis.

Osteoarthritis is a degenerative disease characterized by abnormal neurovascularization at the osteochondral junctions, the regulatory mechanisms of which remain poorly understood. In the present study, a murine osteoarthritic model with augmented neurovascularization at the osteochondral junction is used to examine this under-evaluated facet of degenerative joint dysfunction. Increased extracellular RNA (exRNA) content is identified in neurovascularized osteoarthritic joints. It is found that the amount of exRNA is positively correlated with the extent of neurovascularization and the expression of vascular endothelial growth factor (VEGF). In vitro binding assay and molecular docking demonstrate that synthetic RNAs bind to VEGF via electrostatic interactions. The RNA-VEGF complex promotes the migration and function of endothelial progenitor cells and trigeminal ganglion cells. The use of VEGF and VEGFR2 inhibitors significantly inhibits the amplification of the RNA-VEGF complex. Disruption of the RNA-VEGF complex by RNase and polyethyleneimine reduces its in vitro activities, as well as prevents excessive neurovascularization and osteochondral deterioration in vivo. The results of the present study suggest that exRNAs may be potential targets for regulating nerve and blood vessel ingrowth under physiological and pathological joint conditions.

Macrophage-Derived Extracellular DNA Initiates Heterotopic Ossification.

Heterotopic ossification (HO) severely affects people's lives; however, its pathological mechanism remains poorly understood. Although extracellular DNA (ecDNA) has been shown to play important roles in pathological calcification, its effects in HO development and progression remain unknown. The in vivo rat Achilles tendon injury model and in vitro collagen I calcification model were used to evaluate the effects of ecDNA in the ectopic calcifications and the main cell types involved in those pathological process. Histology, immunofluorescent staining, reverse transcriptase-polymerase chain reaction analysis and micro-computed tomography were used to identify the distribution of macrophage-derived ecDNA and elucidate their roles in HO. The results showed that the amount of ecDNA and ectopic calcification increased significantly and exhibited a strong correlation in the injured tendons of HO model compared with those of the controls, which was accompanied by a significantly increased number of M2 macrophages in the injured tendon. During in vitro co-culture experiments, M2 macrophages calcified the reconstituted type I collagen and ectopic bone collected from the injured tendons of HO rats, while those effects were inhibited by deoxyribonuclease. More importantly, deoxyribonuclease reversed the pathological calcification in the injured rat tendon HO model. The present study showed that ecDNA from M2 macrophages initiates pathological calcification in HO, and the elimination of ecDNA might be developed into a clinical strategy to prevent ectopic mineralization diseases. The use of deoxyribonuclease for the targeted degradation of ecDNA at affected tissue sites provides a potential solution to treat diseases associated with ectopic mineralization.

Transcriptome Profiling of miRNA-mRNA Interactions and Associated Mechanisms in Chemotherapy-Induced Neuropathic Pain.

Chemotherapy-induced neuropathic pain (CINP) is a dose-limiting adverse event affecting 40% of chemotherapy patients. MiRNA-mRNA interaction plays an important role in various processes. However, detailed profiling of miRNA-mRNA interactions in CINP remains unclear. Here, a rat-based CINP model was established using paclitaxel, followed by nociceptive behavioral tests related to mechanical allodynia, thermal hyperalgesia, and cold allodynia. The landscape of miRNA-mRNA interaction in the spinal dorsal horn was investigated through mRNA transcriptomics and small RNA sequencing. Under CINP condition, 86 differentially expressed mRNAs and 56 miRNAs were identified. Gene Set Enrichment Analysis (GSEA), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses indicated the activity of Odorant binding, postsynaptic specialization and synaptic density, extracellular matrix, mitochondrial matrix, retrograde endocannabinoid signaling, and GTPase activity. Protein-protein interaction (PPI), networks of circRNA-miRNA-mRNA, lncRNA-miRNA-mRNA, and TF-genes were demonstrated. We next explored the immune infiltration microenvironment and found a higher infiltration abundance of Th17 and a lower abundance of MDSC in CINP. RT-qPCR and dual-luciferase assays were used to verify the sequencing results, and single-cell analysis based on the SekSeeq database was conducted. Combined with bioinformatics analyses and experimental validations, Mpz, a protein-coding gene specifically expressed in Schwann cells, was found critical in maintaining CINP under miRNA regulation. Therefore, these data highlight the expression patterns of miRNA-mRNA, and the underlying mechanism in the spinal dorsal horn under CINP condition, and Mpz may serve as a promising therapeutic target for patients with CINP.

Fibrotic Matrix Induces Mesenchymal Transformation of Epithelial Cells in Oral Submucous Fibrosis.

Oral submucous fibrosis (OSF) is a potentially malignant disorder of the oral mucosa; however, whether and how the fibrotic matrix of OSF is involved in the malignant transformation of epithelial cells remains unknown. Herein, oral mucosa tissue from patients with OSF, OSF rat models, and their controls were used to observe the extracellular matrix changes and epithelial-mesenchymal transformation (EMT) in fibrotic lesions. Compared with controls, oral mucous tissues from patients with OSF showed an increased number of myofibroblasts, a decreased number of blood vessels, and increased type I and type III collagen levels. In addition, the oral mucous tissues from humans and OSF rats showed increased stiffness, accompanied by increased EMT activities of epithelial cells. The EMT activities of stiff construct-cultured epithelial cells were increased significantly by exogenous piezo-type mechanosensitive ion channel component 1 (Piezo1) activation, and decreased by yes-associated protein (YAP) inhibition. During ex vivo implantation, oral mucosal epithelial cells of the stiff group showed increased EMT activities and increased levels of Piezo1 and YAP compared with those in the sham and soft groups. These results indicate that increased stiffness of the fibrotic matrix in OSF led to increased proliferation and EMT of mucosal epithelial cells, in which the Piezo1-YAP signal transduction is important.

Primary central nervous system diffuse large B-cell lymphoma in fourth ventricle: Case report and literature review.

RATIONALE: Primary central nervous system lymphoma (PCNSL) is rare, especially lymphoma arising in the fourth ventricle. Only a few cases have been reported. We report a case of fourth ventricular lymphoma and review the relevant literature. Characterizing these cases can provide a basis for optimizing the diagnosis and management of fourth ventricle lymphoma. PATIENT CONCERNS: A 48-year-old male with blurred vision, dizziness, staggering persisting for 2 months was admitted. DIAGNOSIS: Preoperative magnetic resonance imaging revealed a space occupying lesion of the fourth ventricle. The patient presented with symptoms of hydrocephalus before surgery, such as memory loss and slurred speech. Pathological analysis following complete resection confirmed the lesion as PCNSL. INTERVENTION: The patient underwent a midline posterior fossa craniotomy. OUTCOMES: The patient symptoms were relieved after surgery. Postoperative chemotherapy was administered with our regular follow-up. Follow-up 9 months after operation indicated a good prognosis. LESSONS: According to the literature, biopsy surgery and subsequent chemotherapy are generally considered as the best treatment options for PCNSL. We believe that for the special location of the fourth ventricle, lymphomas in this site are suitable for the combination of complete resection and subsequent chemotherapy. This approach facilitates tumor resection and reduces possibility of obstructive hydrocephalus.