Is bone marrow biopsy and aspiration still mandatory when 18F-FDG PET/CT is available for the initial assessment of bone marrow metastasis in pediatric Ewing sarcoma?

Purpose: To compare the diagnostic value of 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG PET/CT) and bone marrow biopsy and aspiration (BMBA) for evaluating bone marrow metastases (BMM) in newly diagnosed pediatric Ewing sarcoma (ES). Material and methods: To assess the diagnostic accuracy of 18F-FDG PET/CT against BMBA for marrow infiltration in ES patients, a retrospective analysis encompassed 103 ES patients from the Children's Hospital of Chongqing Medical University, spanning nine years, who underwent both 18F-FDG PET/CT and BMBA at the point of diagnosis. Results: The median age of this study was 9.3(15 days to 17.1 years), 52(50.5%) patients were male. Among the cohort, 8 subjects received a BMM diagnosis via marrow cytology or histopathology, concomitant with positive 18F-FDG PET/CT findings. An additional 4 patients were identified with BMM solely through 18F-FDG PET/CT. No cytologically or histologically positive BMM were found in PET/CT-negative patients. Therefore, within this selected sample group, the 18F-FDG PET/CT imaging technique exhibited sensitivity of 100% and specificity of 95.8%. The five-year overall survival rate decreased from 57.5% among the entire cohort of patients to a mere 30% for individuals suffering from BMM. Conclusion: Given these findings, the prevailing reliance on BMBA warrants reevaluation when 18F-FDG PET/CT is available, potentially heralding a shift towards less invasive diagnostic modalities in the management of ES.

Treatment of metastatic TFE3 microphthalmia transcription factor translocation renal cell carcinoma: a case report.

Background: Microphthalmia-associated transcription factor/transcription factor E (MiTF/TFE) translocation renal cell carcinoma (RCC) is a rare type of non-clear cell RCC (nccRCC), which is more common in females. Currently, there is no standardized treatment for advanced metastatic microphthalmia translocation RCC (MiT-RCC). The main treatment modalities include surgery, chemotherapy, immunotherapy, anti-vascular endothelial growth factor or vascular endothelial growth factor receptor (VEGFR) inhibitors, mammalian target of rapamycin (mTOR) inhibitors, and targeted therapy against the mesenchymal-epithelial transition (MET) factor signaling pathway. Case Description: We present the case of an 8-year-old male patient with hematuria and paroxysmal urinary pain. Based on tumor genetic testing results and targeted drug matching analysis, the patient underwent tumor biopsy, tumor radical surgery with vascular osteotomy, and cervicothoracic lymph node dissection. The patient was then treated with a combination of immunotherapy [sintilimab, a drug directed against programmed cell death receptor-1 (PD-1)] and VEGFR tyrosine kinase inhibitor (TKI) (from pazopanib to sunitinib). Throughout the 10 cycles of conventional chemotherapy (seven courses of sintilimab since the start of the third chemotherapy treatment), the patient's condition remained stable, with no tumor recurrence at the primary site. However, in the later stages, the patient developed a large amount of ascites, and the family requested discontinuation of treatment, ultimately leading to the patient's death. Conclusions: In this case report, we summarize the therapeutic strategy of a young patient with metastatic transcription factor E3 (TFE3) MiT-RCC. For this disease, early immunotherapy and the use of precision-targeted drugs may have a favorable impact on the survival prognosis of the patient but may still be of less benefit in children with advanced multiple metastases. Therefore, further research on tumor driver genes, among other treatment components, is urgently needed to improve precision therapy.

Bioactive materials from berberine-treated human bone marrow mesenchymal stem cells promote alveolar bone regeneration by regulating macrophage polarization.

Alveolar bone regeneration has been strongly linked to macrophage polarization. M1 macrophages aggravate alveolar bone loss, whereas M2 macrophages reverse this process. Berberine (BBR), a natural alkaloid isolated and refined from Chinese medicinal plants, has shown therapeutic effects in treating metabolic disorders. In this study, we first discovered that culture supernatant (CS) collected from BBR-treated human bone marrow mesenchymal stem cells (HBMSCs) ameliorated periodontal alveolar bone loss. CS from the BBR-treated HBMSCs contained bioactive materials that suppressed the M1 polarization and induced the M2 polarization of macrophages in vivo and in vitro. To clarify the underlying mechanism, the bioactive materials were applied to different animal models. We discovered macrophage colony-stimulating factor (M-CSF), which regulates macrophage polarization and promotes bone formation, a key macromolecule in the CS. Injection of pure M-CSF attenuated experimental periodontal alveolar bone loss in rats. Colony-stimulating factor 1 receptor (CSF1R) inhibitor or anti-human M-CSF (M-CSF neutralizing antibody, Nab) abolished the therapeutic effects of the CS of BBR-treated HBMSCs. Moreover, AKT phosphorylation in macrophages was activated by the CS, and the AKT activator reversed the negative effect of the CSF1R inhibitor or Nab. These results suggest that the CS of BBR-treated HBMSCs modulates macrophage polarization via the M-CSF/AKT axis. Further studies also showed that CS of BBR-treated HBMSCs accelerated bone formation and M2 polarization in rat teeth extraction sockets. Overall, our findings established an essential role of BBR-treated HBMSCs CS and this might be the first report to show that the products of BBR-treated HBMSCs have active effects on alveolar bone regeneration.

Single-cell transcriptome sequencing reveals tumor heterogeneity in family neuroblastoma.

Neuroblastoma(NB) is the most common extracranial solid tumor in childhood, and it is now believed that some patients with NB have an underlying genetic susceptibility, which may be one of the reasons for the multiplicity of NB patients within a family line. Even within the same family, the samples show great variation and can present as ganglioneuroblastoma or even benign ganglioneuroma. The genomics of NB is still unclear and more in-depth studies are needed to reveal its key components. We first performed single-cell RNA sequencing(sc-RNAseq) analysis on clinical specimens of two family neuroblastoma(FNB) and four sporadic NB cases. A complete transcriptional profile of FNB was constructed from 18,394 cells from FNB, and we found that SDHD may be genetically associated with FNB and identified a prognostic related CAF subtype in FNB: Fib-4. Single-cell flux estimation analysis (scFEA) results showed that malignant cells were associated with arginine spermine, oxaloacetate and hypoxanthine, and that malignant cells metabolize lactate at lower levels than T cells. Our study provides new resources and ideas for the development of the genomics of family NB, and the mechanisms of cell-to-cell interactions and communication and the metabolic landscape will provide new therapeutic targets.

Effectiveness of Home-Based Telerehabilitation Interventions for Dysphagia in Patients With Head and Neck Cancer: Systematic Review.

BACKGROUND: Multimodal treatment-induced dysphagia has serious negative effects on survivors of head and neck cancer. Owing to advances in communication technologies, several studies have applied telecommunication-based interventions that incorporate swallowing exercises, education, monitoring, feedback, self-management, and communication. It is especially urgent to implement home-based remote rehabilitation in the context of the COVID-19 pandemic. However, the optimal strategy and effectiveness of remote interventions are unclear. OBJECTIVE: This systematic review aimed to examine the evidence regarding the efficacy of telerehabilitation for reducing physiological and functional impairments related to swallowing and for improving adherence and related influencing factors among head and neck cancer survivors. METHODS: The PubMed, MEDLINE, CINAHL, Embase, and Cochrane Library databases were systematically searched up to July 2023 to identify relevant articles. In total, 2 investigators independently extracted the data and assessed the methodological quality of the included studies using the quality assessment tool of the Joanna Briggs Institute. RESULTS: A total of 1465 articles were initially identified; ultimately, 13 (0.89%) were included in the systematic review. The quality assessment indicated that the included studies were of moderate to good quality. The results showed that home-based telerehabilitation improved the safety of swallowing and oral feeding, nutritional status, and swallowing-related quality of life; reduced negative emotions; improved swallowing rehabilitation adherence; was rated by participants as highly satisfactory and supportive; and was cost-effective. In addition, this review investigated factors that influenced the efficacy of telerehabilitation, which included striking a balance among swallowing training strategy, intensity, frequency, duration, and individual motor ability; treating side effects of radiotherapy; providing access to medical, motivational, and educational information; providing feedback on training; providing communication and support from speech pathologists, families, and other survivors; and addressing technical problems. CONCLUSIONS: Home-based telerehabilitation has shown great potential in reducing the safety risks of swallowing and oral feeding, improving quality of life and adherence, and meeting information needs for dysphagia among survivors of head and neck cancer. However, this review highlights limitations in the current literature, and the current research is in its infancy. In addition, owing to the diversity of patient sociodemographic, medical, physiological and functional swallowing, and behavioral factors, we recommend the development of tailored telemedicine interventions to achieve the best rehabilitation effects with the fewest and most precise interventions.

Dual ultrasound-guided totally implantable venous access ports via the right internal jugular vein in pediatric patients with cancer: a preliminary experience in a single institution.

Objective: To assess the efficacy and safety of dual ultrasound-guided (DUG) totally implantable venous access port (TIVAP) implantation (namely, using ultrasound-guided percutaneous puncture with transesophageal echocardiography-guided catheterization) via the right internal jugular vein (IJV) in pediatric patients with cancer. Methods: Fifty-five children with cancer requiring chemotherapy underwent DUG-TIVAP implantation via the right IJV. Clinical data were recorded, including the procedure success rate, first attempt success rate, and perioperative and postoperative complications. Results: All 55 cases were successfully operated on. The first puncture success rate was 100%. The operation time was 22-41 min, with a mean time of 30.8±5.5 min. The mean TIVAP implantation time was 253±145 days (range 42-520 days). There were no perioperative complications. The postoperative complication rate was 5.4% (3/55), including skin infections around the port in one case, catheter-related infection in one case, and fibrin sheath formation in one case. The ports were all preserved after anti-infection or thrombolytic therapy. No unplanned port withdrawal was recorded in this study. Conclusions: DUG-TIVAP implantation is a technique with a high success rate and a low complication rate; therefore, it provides an alternative for children with cancer. Further randomized controlled studies are needed to confirm the efficacy and safety of DUG-TIVAP via the right IJV in children.

Emerging roles of O-glycosylation in regulating protein aggregation, phase separation, and functions.

Protein O-glycosylation is widely identified in various proteins involved in diverse biological processes. Recent studies have demonstrated that O-glycosylation plays crucial and multifaceted roles in modulating protein amyloid aggregation and liquid-liquid phase separation (LLPS) under physiological conditions. Dysregulation of these processes is closely associated with human diseases such as neurodegenerative diseases (NDs) and cancers. In this review, we first summarize the distinct roles of O-glycosylation in regulating pathological aggregation of different amyloid proteins related to NDs and elaborate the underlying mechanisms of how O-glycosylation modulates protein aggregation kinetics, induces new aggregated structures, and mediates the pathogenesis of amyloid aggregates under diseased conditions. Furthermore, we introduce recent discoveries on O-GlcNAc-mediated regulation of synaptic LLPS and phase separation potency of low-complexity domain-enriched proteins. Finally, we identify challenges in future research and highlight the potential for developing new therapeutic strategies of NDs by targeting protein O-glycosylation.

Metabolic Glycan Labeling in Primary Neurons Enabled by Unnatural Sugars with No S-Glyco-Modification.

It is of great interest to probe glycosylation in primary neuron cultures. However, per-O-acetylated clickable unnatural sugars, which have been routinely utilized in metabolic glycan labeling (MGL) for analyzing glycans, showed cytotoxicity to cultured primary neurons and thus led to the speculation that MGL was not compatible with primary neuron cell cultures. Here, we uncovered that neuron cytotoxicity of per-O-acetylated unnatural sugars was related to their reactions with protein cysteines via non-enzymatic S-glyco-modification. The modified proteins were enriched in biological functions related to microtubule cytoskeleton organization, positive regulation of axon extension, neuron projection development, and axonogenesis. We thus established MGL in cultured primary neurons without cytotoxicity using S-glyco-modification-free unnatural sugars including ManNAz, 1,3-Pr2ManNAz, and 1,6-Pr2ManNAz, which allowed for visualization of cell-surface sialylated glycans, probing the dynamics of sialylation, and large-scale identification of sialylated N-linked glycoproteins and the modification sites in primary neurons. Particularly, a total of 505 sialylated N-glycosylation sites distributed on 345 glycoproteins were identified by 1,6-Pr2ManNAz.

Morphometric analysis of paired fibula and mandible for optimal fibular mandibular reconstruction in a Chinese population.

To analyze the morphology of paired fibula and mandible aiming to choose optimal fibular segments for mandibular reconstruction in a Chinses population. A total of 118 cases of paired mandible and fibula was collected. All patients were received preoperative cone beam CT (CBCT) scans for mandibular evaluation and CT-angiographical (CTA) examination of the bilateral lower legs, respectively. The cross-sectional morphological differences between proximal (Side P), middle (Side M) and distal (Side D) segments of fibula and anterior, premolar and molar areas of mandible were compared. The most frequent cross-sectional shape at Side D, Side M and Side P portion of fibula was circular (75.4%), triangular (67.8%) and circular (49.2%), respectively. In anterior, premolar and molar areas of mandible, the most of the cross-section was s-shape (90.82%), straight (83.64%) and oblique (91.89%), respectively. The height and width of upper one third (W1) at Side M were significantly larger than those of Side D and Side P (p < 0.0001). There was significantly difference of width of lower one third (W2) among three groups (p < 0.0001). As for the height and widths of mandible, there was significant difference among anterior, premolar and molar regions (p < 0.0001). The rate of height between Side M of fibula and mandible (H (Side M/area)) was significantly larger than H (Side D/area) and H (Side P/area) (p < 0.01). The ratio of W1 between Side D of fibula and mandible (W1 (Side D/area)) was significantly larger than that of W1 (Side M/area) and W1 (side P/area) (p < 0.05). As for the ratio of W2 between fibula and mandible (W2 (plane/area)), there was significant difference among groups (p < 0.01). The distal and middle segments of fibula were suitable for reconstructing the anterior area of mandible and the proximal segment of fibula was more compatible with the premolar and molar areas of mandible.Clinical Relevance Presurgical morphometric analysis of paired fibula and mandible aids for optimal fibular-based mandibular reconstruction.

Intraoral versus transcervical approaches in mandibular reconstruction with free flaps: A retrospective study.

This study aims to investigate the clinical and functional differences between intraoral and transcervical approaches for segmental mandible resection and reconstruction with free flaps. Patients diagnosed as benign and low-grade mandibular malignant tumors without neck dissections were retrospectively reviewed and divided into intraoral and transcervical groups. Patients of intraoral group underwent intraoral mandibulectomy and vascular anastomosis was performed through a 2-cm submandibular incision, while traditional submandibular approach was used in transcervical group. Clinical characteristics of two groups were assessed including body mass index (BMI), defect types and number of fibular segments, as well as perioperative variables such as operation time, blood loss, drainage volume. The score of appearance, swallowing and speech using the University of Washington Quality of Life Questionnaire (UW-QOL) was recorded and analyzed 6-month postoperatively. A total of 14 patients in intraoral group and 21 patients in transcervical group was collected, respectively. In intraoral group, intraoperative blood loss and postoperative drainage volume were significantly reduced in comparison with transcervical group (p = 0.0146, p = 0.0017; respectively). The score of appearance was 87.50 ± 12.97 in intraoral group, which was significantly higher than 64.29 ± 12.68 in transcervical group (p < 0.0001). Similar results were found in patients of subtype Class II mandibular defect between two groups. However, patients of intraoral group had a significant increase in operative time and a comparable amount of intraoperative blood loss (p = 0.0472, p = 0.1434; respectively). Within the limitations of the study it seems that an intraoral approach combined with a 2-cm submandibular incision should be preferred over a transcervical approach for segmental mandibulectomy and free flap reconstruction whenever appropriate.

Vascular Analysis of Soft Tissues Around the Bone Lesion in Osteoradionecrosis, Medication-Related Osteonecrosis, and Infectious Osteomyelitis of the Jaw.

OBJECTIVE: The histopathological differences of the surrounding soft tissues in osteoradionecrosis of the jaw, medication-related osteonecrosis of the jaw as well as infectious osteomyelitis of the jaw patients were rarely investigated. Here, we focused on the vascular microarchitecture of the soft tissues around bone lesion and compared the microvessel difference of ORNJ, MRONJ, and IOMJ in a quantitative fashion. METHODS: A series of consecutive patients diagnosed as ORNJ, MRONJ, and acute/chronic IOMJ was retrospectively reviewed. All cases received preoperative cone bean computed tomography scans. Immunohistochemistry of CD34 was performed with the streptavidin-peroxidase method and the variables including vascular density, vascular area fraction, mean vessel lumen area, perimeter and diameter of the vessels as well as percentage of lumen less than 400 µm2 were analyzed. RESULTS: The results showed that the vascular-like structures were visible in more cases of acute/chronic IOMJ compared with ORNJ and MRONJ by hematoxylin-eosin staining. Quantitively, our results demonstrated the decreased vascular density, mean perimeter and diameter of the vessels but increased percentage of small vessels in ORNJ and MRONJ patients in contrast with IOMJ patients. CONCLUSIONS: Hypovascularity of surrounding soft tissues could play important roles in the etiology of IOMJ, ORNJ, and MRONJ, and microvessel profile may be a useful pathological diagnostic indicator to differentiate these 3 types of OMJ.

A model for the uptake of advance care planning in older cancer adults: a scoping review.

BACKGROUND AND AIMS: Advance care planning (ACP) might assist older cancer patients in expressing their goals, values, and care preferences; yet, the ACP uptake rates in this group are low. The goal of this study is to discover factors that influence ACP uptake in older cancer adults and to construct a model that integrates these factors. METHODS: Using Arksey and O' Malley's methodology, we systematically searched seven electronic databases of ACP literature in older cancer adults from inception to March 2022. To identify factors linked to ACP uptake in elderly cancer patients, researchers used a pre-piloted extraction form. There were two phases to the thematic analysis of the labeled factors. First, factors were grouped into one of three categories using a directed content analysis approach: patient context, provider context, or mechanism. Second, we took both a deductive and inductive thematic approach to identifying and coding contributing factors in each category to identify themes and subthemes. Deductive coding was undertaken using the Andersen's Behavioral Model of Health Services Utilization. Finally, results were visualized into a conceptual model. RESULTS: In the including 37 articles, 131 factors were extracted. Thematic analysis of patient context factors (n = 72) showed that ACP uptake in older cancer adults is associated with predisposing characteristics, enabling resources and need. Factors attributed to provider context (n = 28) concerned predisposing characteristics and enabling resources. Mechanism factors (n = 31) are related to perceived value and patient trust, and the C-ACP uptake model was created. CONCLUSION: ACP uptake in older cancer patients is commonly influenced by patient-provider-related contextual factors, and highlights the fact that ACP uptake is more likely to be mediated through both perceived value and patient trust. This review serves as a resource for providers exploring ACP implementation options in older cancer adults.

Selective inhibition reveals the regulatory function of DYRK2 in protein synthesis and calcium entry.

The dual-specificity tyrosine phosphorylation-regulated kinase DYRK2 has emerged as a critical regulator of cellular processes. We took a chemical biology approach to gain further insights into its function. We developed C17, a potent small-molecule DYRK2 inhibitor, through multiple rounds of structure-based optimization guided by several co-crystallized structures. C17 displayed an effect on DYRK2 at a single-digit nanomolar IC50 and showed outstanding selectivity for the human kinome containing 467 other human kinases. Using C17 as a chemical probe, we further performed quantitative phosphoproteomic assays and identified several novel DYRK2 targets, including eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) and stromal interaction molecule 1 (STIM1). DYRK2 phosphorylated 4E-BP1 at multiple sites, and the combined treatment of C17 with AKT and MEK inhibitors showed synergistic 4E-BP1 phosphorylation suppression. The phosphorylation of STIM1 by DYRK2 substantially increased the interaction of STIM1 with the ORAI1 channel, and C17 impeded the store-operated calcium entry process. These studies collectively further expand our understanding of DYRK2 and provide a valuable tool to pinpoint its biological function.

Optical Cell Tagging for Spatially Resolved Single-Cell RNA Sequencing.

Single-cell RNA sequencing (scRNA-seq) has emerged as a powerful tool for profiling gene expression of distinct cell populations at the single-cell level. However, the information of the positions of cells within the multicellular samples is missing in scRNA-seq datasets. To overcome this limitation, we herein develop OpTAG (optical cell tagging) as a new chemical platform for attaching functional tags onto cell surfaces in a spatially resolved manner. With OpTAG, we establish OpTAG-seq, which enables spatially resolved scRNA-seq. We apply OpTAG-seq to investigate the spatially defined transcriptional program in migrating cancer cells and identified a list of genes that are potential regulators for cancer cell migration and invasion. OpTAG-seq provides a convenient method for mapping cellular heterogeneity with spatial information within multicellular biological systems.

A Novel Classification of Relationship Between Nasal Septum and Inferior Turbinate Associated With Nasal Airway Obstruction in Patients With Unilateral Alveolar Cleft.

OBJECTIVE: This study aims to investigate nasal morphologies associated with nasal airway obstruction in unilateral alveolar cleft patients. METHODS: A total of 234 unilateral alveolar cleft cases were performed cone beam computed tomography scans. The digital imaging and communication in medicine data were imported into Simplant Pro software. The radiographic features including nasal septum deviation and inferior turbinate hypertrophy as well as nasal airway volume and sinusitis were analyzed. RESULTS: A new radiographic classification of relationship between nasal septum and inferior turbinate (NS-IT) on the cleft side was proposed and three types of NS-IT relationship (type I, II and III) were identified in 234 cases. The statistical analysis revealed that the nasal airway volume on non-cleft side was significantly higher than that on cleft side in each of three types (P  < 0.0001), while no difference of nasal airway volume on non-cleft side was found among three types. In addition, the nasal airway volume on non-cleft side in type I and II was significantly higher than that in type III (P < 0.0001). Also, type III presented higher rate of maxillary sinusitis (P = 0.0154) and ethmoid sinusitis on cleft side (P = 0.0490) than type I and II. The other indexes including clinical variances were not significant among three types. CONCLUSIONS: Unilateral alveolar cleft patients with type III NS-IT relationship could have nasal airway obstruction and higher rate of maxillary and ethmoid sinusitis on cleft side, which may be taken into account at primary cleft repair and alveolar bone grafting treatment.

Human amnion-derived mesenchymal stem cells promote osteogenic differentiation of lipopolysaccharide-induced human bone marrow mesenchymal stem cells via ANRIL/miR-125a/APC axis.

BACKGROUND AND AIM: Periodontitis is a chronic inflammatory disease inducing the absorption of alveolar bone and leading to tooth loss. Human amnion-derived mesenchymal stem cells (HAMSCs) have been used for studying inflammatory processes. This study aimed to explore the role of long noncoding RNA (lncRNA) antisense noncoding RNA in the INK4 locus (ANRIL) in HAMSC-driven osteogenesis in lipopolysaccharide (LPS)-induced human bone marrow mesenchymal stem cells (HBMSCs). METHODS: The cells were incubated with a co-culture system. Reactive oxygen species (ROS) level and superoxide dismutase (SOD) activity were used to detect the oxidative stress level. Flow cytometry was performed to determine cell proliferation. The alkaline phosphatase (ALP) activity, Alizarin red assay, cell transfection, and rat mandibular defect model were used to evaluate the osteogenic differentiation. Quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR), Western blot analysis, dual-luciferase reporter assay, and immunofluorescence staining were used to evaluate the molecular mechanisms. RESULTS: This study showed that HAMSCs promoted the osteogenesis of LPS-induced HBMSCs, while the ANRIL level in HBMSCs decreased during co-culture. ANRIL had no significant influence on the proliferation of LPS-induced HBMSCs. However, its overexpression inhibited the HAMSC-driven osteogenesis in vivo and in vitro, whereas its knockdown reversed these effects. Mechanistically, this study found that downregulating ANRIL led to the overexpression of microRNA-125a (miR-125a), and further contributed to the competitive binding of miR-125a and adenomatous polyposis coli (APC), thus significantly activating the Wnt/ß-catenin pathway. CONCLUSION: The study indicated that HAMSCs promoted the osteogenic differentiation of LPS-induced HBMSCs via the ANRIL/miR-125a/APC axis, and offered a novel approach for periodontitis therapy.

Polydopamine-Ag composite surface guides HBMSCs adhesion and proliferation.

Human bone marrow mesenchymal stem cells (HBMSCs) are regarded as an important resource in the field of maxillofacial bone regeneration because of their favorable properties when compared with other stem cells. Hence, finding suitable materials that could extend the application of HBMSCs has become an emerging medical topic and socioeconomic problem. In this work, polydopamine (PDA)-Ag surface was fabricated by PDA assisted photoreduction method, and the obtained PDA-Ag composite surface significantly promoted HBMSCs adhesion and proliferation. This effect is highly related to the amount of Ag nanoparticles (Ag NPs) present on the PDA surface. The behavior of HBMSCs on PDA-Ag surface could be spatially manipulated by controlling the distribution of Ag NPs on PDA surface (by controlling UV light). The general adhesion property allows the PDA-Ag surface to be fabricated on various substrates, making it a simple, general and controllable method for the fabrication of bioactive surface for HBMSCs.

Abnormal macrophage polarization impedes the healing of diabetes-associated tooth sockets.

Patients with poorly controlled type 2 diabetes mellitus (T2DM) often experience delayed tooth extraction socket (TES) healing. Delayed healing is often associated with an aberrant inflammatory response orchestrated by either M1 pro-inflammatory or M2 anti-inflammatory macrophages. However, the precise mechanism for the attenuated TES healing remains unclear. Here we used diet-induced T2DM mice as a model to study TES. Compared with the control group, the T2DM group showed delayed TES healing and diminished expression of osteogenic and angiogenic genetic profiles. Meanwhile, we detected a more inflammatory profile, with more M1 macrophages and TNF-α expression and less M2 macrophages and PPARγ expression, in TES in the T2DM group when compared to control mice. In vitro co-culture models showed that M1 macrophages inhibited the osteogenic capacity of bone marrow stromal cells and the angiogenic capacity of endothelial cells while M2 macrophages showed an opposite effect. In addition, we constructed a gelatin/ß-TCP scaffold with IL-4 to induce macrophage transformation towards M2 polarization. In vitro analyses of the hybrid scaffold revealed sustained release of IL-4 and a phenotype switch to M2 macrophages. Finally, we demonstrated that sustained IL-4 release significantly increased expression of osteogenic and angiogenic genetic profiles and improved TES healing in T2DM mice. Together, we report that increased M1 and decreased M2 macrophage polarization may be responsible for delayed TES healing in T2DM patients through abnormal expression of TNF-α and PPARγ. This imbalance negatively influences osteogenesis and angiogenesis, two of the most important biological factors in bone wound healing. Enhancing M2 macrophage polarization with IL-4 delivery system may represent a potential strategy for promoting the healing of TES in T2DM patients.

Parathyroid hormone ameliorates osteogenesis of human bone marrow mesenchymal stem cells against glucolipotoxicity through p38 MAPK signaling.

Diabetes mellitus (DM)-induced glucolipotoxicity is a factor strongly contributing to alveolar bone deficiency. Parathyroid hormone (PTH) has been identified as a main systemic mediator to balance physiological calcium in bone. This study aimed to uncover PTH's potential role in ameliorating the osteogenic capacity of human bone marrow mesenchymal stem cells (HBMSCs) against glucolipotoxicity. Optimal PTH concentrations and high glucose and palmitic acid (GP) were administered to cells, followed by alkaline phosphatase (ALP) staining and ALP activity assay. Quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) and Immunoblot were carried out for assessing mRNA and protein amounts, respectively. Cell counting kit-8 (CCK-8) and flow cytometry were performed for quantitating cell proliferation. Osteogenesis and oxidative stress were determined, and the involvement of mitogen-activated protein kinase (MAPK) signaling was further verified. About 1-50 mmol/ml GP significantly inhibited the osteogenic differentiation of HBMSCs. 10-9 mol/L PTH was found to be the optimal concentration for HBMSC induction. PTH had no effects on HBMSC proliferation, with or without GP treatment. PTH reversed inadequate osteogenesis and excessive oxidative stress in GP-treated HBMSCs. Mechanistically, PTH activated p38 MAPK signaling, while inhibiting p38 MAPK-suppressed PTH's beneficial impacts on HBMSCs. Collectively, PTH promotes osteogenic differentiation in HBMSCs against glucolipotoxicity via p38 MAPK signaling.