VE-Cadherin and Anastomosis of Blood Vessels Formed by Dental Stem Cells

It is known that dental pulp stem cells (DPSCs) can be induced to differentiate into vasculogenic endothelial (VE) cells. However, the process that results in sprouting and anastomosis of DPSC-derived vessels remains unclear. Here, we performed studies to understand the mechanisms underpinning the anastomosis of the host vasculature with blood vessels generated by DPSCs (a model for mesenchymal stem cells). VE-cadherin-silenced primary human DPSCs seeded in tooth slice/scaffolds and transplanted into the subcutaneous space of immunodeficient mice generated fewer functional blood vessels (i.e., anastomosed with the host vasculature) than control DPSCs transduced with scrambled sequences. Both VE-cadherin-silenced and mitogen-activated protein kinase kinase 1 (MEK1)-silenced cells showed a decrease in the number of capillary sprouts in vitro. Interestingly, DPSC stably transduced with a VE-cadherin reporter demonstrated that vascular endothelial growth factor (VEGF) induces VE-cadherin expression in sprouting DPSCs undergoing anastomosis, but not in quiescent DPSCs. To begin to understand the mechanisms regulating VE-cadherin, we stably silenced MEK1 and observed that VEGF was no longer able to induce VE-cadherin expression and capillary sprout formation. Notably ERG, a transcriptional factor downstream from MEK/ERK, binds to the promoter region of VE-cadherin (chip assay) and is induced by VEGF in DPSCs. Collectively, these data defined a signaling pathway triggered by VEGF that results in phosphorylation of MEK1/ERK and activation of ERG leading to expression of VE-cadherin, which is required for anastomosis of DPSC-derived blood vessels. In conclusion, these results unveiled a signaling pathway that enables the generation of functional blood vessels upon vasculogenic differentiation of DPSCs.

Oral Rehabilitation of Patients Sustaining Orofacial Injuries: The UPenn Initiative

Tissue injuries in the oral and maxillofacial structures secondary to trauma, warfare, ablative cancer, and benign tumor surgery result in significant losses of speech, masticatory and swallowing functions, aesthetic deformities, and overall psychological stressors and compromise. Optimal oral rehabilitation remains a formidable challenge and an unmet clinical need due to the influence of multiple factors related to the physiologic limitations of tissue repair, the lack of site and function-specific donor tissues and constructs, and an integrated team of multidisciplinary professionals. The advancements in stem cell biology, biomaterial science, and tissue engineering technologies, particularly the 3-dimensional bioprinting technology, together with digital imaging and computer-aided design and manufacturing technologies, have paved the path for personalized/precision regenerative medicine. At the University of Pennsylvania, we have launched the initiative to integrate multidisciplinary health professionals and translational/clinical scientists in medicine, dentistry, stem cell biology, tissue engineering, and regenerative medicine to develop a comprehensive, patient-centered approach for precision and personalized reconstruction, as well as oral rehabilitation of patients sustaining orofacial tissue injuries and defects, especially oral cancer patients.

S100A8/A9 promotes MMP-9 expression in the fibroblasts from cardiac rupture after myocardial infarction by inducing macrophages secreting TNFα

OBJECTIVE

Inflammation and extracellular matrix degradation play a role in cardiac rupture (CR) after myocardial infarction (MI). It has been found that the expression of inflammatory cytokine S100A8/A9 was elevated in acute MI patients, whereas its impact in CR after infarction remains unclear.

PATIENTS AND METHODS

Samples from cardiac tissue and peripheral blood of patients with CR after MI, MI, patients without CR, and healthy control (cardiotrauma) were collected to test the expressions of S100A8/A9, p-p65, and MMP-9. Co-culture system for HCF cells and macrophages were established to identify the impact of hypoxia-ischemia on the expressions of S100A8/A9 and TNFα. S100A9 and/or TNFα blocking agent were applied to examine the effect on macrophages migration, expressions of S100A8, S100A9, and TNFα. Western blot was adopted to determine levels of p-p65 and MMP-9 protein after the inhibition of S100A9 and/or TNFα.

RESULTS

Compared with healthy control and non-CR patients, serum S100A8/A9 and MMP-9 levels were elevated in cardiac tissues of CR patients, while S100A8/A9, p-p65, and MMP-9 were also overexpressed. Hypoxia-ischemia significantly caused the increasing levels of S100A8/A9 and TNFα in macrophages (p < 0.05). The blockade of S100A9 and/or TNFα suppressed the activation and migration of macrophages. The inhibition of S100A9 expression also decreased the secretion of TNFα in macrophages, while the suppression of TNFα showed no significant impact on S100A8 and S100A9 levels. Downregulation of TNFα or NF-κB markedly declined p-p65 and MMP-9 protein levels in HCF cells from co-culture system or single culture, whereas the blockade of S100A9 only reduced their expressions in co-cultured HCF cells.

CONCLUSIONS

The level of S100A8/A9 was upregulated in MI patients with CR. S100A8/A9 induced the activation of NF-κB and expression of MMP-9 protein in HCF cells through facilitating secretion of TNFα from macrophages, which may play a role in triggering extracellular matrix degradation and CR.

Correction to: Rehmanniae Radix Preparata suppresses bone loss and increases bone strength through interfering with canonical Wnt/β-catenin signaling pathway in OVX rats

There was a mistake in the part of OVX rats model and RRP intervention in the original publication.

Dependence of the squeezing and anti-squeezing factors of bright squeezed light on the seed beam power and pump beam noise

We demonstrate the dependence of the squeezing and anti-squeezing factors on the seed beam power at different pump beam noise levels. The results indicate that a seed field injected into the optical parametric amplifier (OPA) dramatically degenerates the squeezing factor due to noise coupling between the pump and seed fields, even if both the pump and seed fields reach the shot noise limit. The squeezing and anti-squeezing factors are immune to the pump beam noise due to no noise coupling when the system operates for the generation of squeezed vacuum states. The squeezing factor degrades gradually as the pump beam intensity noise and seed beam power is increased. The influence of the two orthogonal quadrature variations is mutually independent of each other.

Rehmanniae Radix Preparata suppresses bone loss and increases bone strength through interfering with canonical Wnt/β-catenin signaling pathway in OVX rats

Rehmanniae Radix Preparata (RRP) improves bone quality in OVX rats through the regulation of bone homeostasis via increasing osteoblastogenesis and decreasing osteoclastogenesis, suggesting it has a potential for the development of new anti-osteoporotic drugs.

INTRODUCTION

Determine the anti-osteoporotic effect of RRP in ovariectomized (OVX) rats and identify the signaling pathway involved in this process.

METHODS

OVX rats were treated with RRP aqueous extract for 14 weeks. The serum levels of tartrate-resistant acid phosphatase (TRAP), receptor activator of nuclear factor kappa-Β ligand (RANKL), alkaline phosphatase (ALP), and osteoprotegerin (OPG) were determined by ELISA. Bone histopathological alterations were evaluated by H&E, Alizarin red S, and Safranin O staining. Bone mineral density (BMD) and bone microstructure in rat femurs and lumbar bones were determined by dual-energy X-ray absorptiometry and micro-computed tomography. Femoral bone strength was detected by a three-point bending assay. The expression of Phospho-glycogen synthase kinase 3 beta (p-GSK-3β), GSK-3β, Dickkopf-related protein 1 (DKK1), cathepsin K, OPG, RANKL, IGF-1, Runx2, β-catenin, and p-β-catenin was determined by western blot and/or immunohistochemical staining.

RESULTS

Treatment of OVX rats with RRP aqueous extract rebuilt bone homeostasis demonstrated by increasing the levels of OPG as well as decreasing the levels of TRAP, RANKL, and ALP in serum. Furthermore, RRP treatment preserved BMD and mechanical strength by increasing cortical bone thickness and epiphyseal thickness as well as improving trabecular distribution in the femurs of OVX rats. In addition, RRP downregulated the expression of DKK1, sclerostin, RANKL, cathepsin K, and the ratio of p-β-catenin to β-catenin, along with upregulating the expression of IGF-1, β-catenin, and Runx2 and the ratio of p-GSK-3β to GSK-3β in the tibias and femurs of OVX rats. Echinacoside, jionoside A1/A2, acetoside, isoacetoside, jionoside B1, and jionoside B2 were identified in the RRP aqueous extract.

CONCLUSION

RRP attenuates bone loss and improves bone quality in OVX rats partly through its regulation of the canonical Wnt/β-catenin signaling pathway, suggesting that RRP has the potential to provide a new source of anti-osteoporotic drugs.

Pulp Stem Cell-Mediated Functional Pulp Regeneration

The preservation of vital dental pulp with vasculature and nerve components remains one of the most significant challenges in modern dentistry. Due to the immense potential for neurovascularization, mesenchymal stem cell (MSC) transplantation has shown emerging promise in regenerative medicine and dental translational practice. Actually, pulp mesenchymal stem cells, including postnatal dental pulp stem cells (from permanent teeth) and stem cells from human exfoliated deciduous teeth, possess unique properties based on their origins from neural crest or glial cells. Furthermore, they reside in a neurovascular niche and have the potential for neurogenesis, angiogenesis, and neurovascular inductive activity. According to current pulp regeneration strategies, pulp stem cell-mediated approaches to regeneration have demonstrated convincing evidence that they can rebuild the complex histologic structure of native pulp in situ with highly organized physiologic patterns or even achieve de novo regeneration of complete dental pulp tissues. More importantly, recent clinical studies emphasized in situ neurovascularization outcomes in successful regeneration of vitalized pulp via pulp stem cell transplantation. In this review, we summarize recent breakthroughs in pulp stem cell-mediated pulp regeneration, emphasizing the crucial achievement of neurovascularization. This functional pulp regeneration represents an innovative and promising approach for future regenerative endodontics.

Computational prediction and analysis of species-specific fungi phosphorylation via feature optimization strategy

Protein phosphorylation is a reversible and ubiquitous post-translational modification that primarily occurs at serine, threonine and tyrosine residues and regulates a variety of biological processes. In this paper, we first briefly summarized the current progresses in computational prediction of eukaryotic protein phosphorylation sites, which mainly focused on animals and plants, especially on human, with a less extent on fungi. Since the number of identified fungi phosphorylation sites has greatly increased in a wide variety of organisms and their roles in pathological physiology still remain largely unknown, more attention has been paid on the identification of fungi-specific phosphorylation. Here, experimental fungi phosphorylation sites data were collected and most of the sites were classified into different types to be encoded with various features and trained via a two-step feature optimization method. A novel method for prediction of species-specific fungi phosphorylation-PreSSFP was developed, which can identify fungi phosphorylation in seven species for specific serine, threonine and tyrosine residues (http://computbiol.ncu.edu.cn/PreSSFP). Meanwhile, we critically evaluated the performance of PreSSFP and compared it with other existing tools. The satisfying results showed that PreSSFP is a robust predictor. Feature analyses exhibited that there have some significant differences among seven species. The species-specific prediction via two-step feature optimization method to mine important features for training could considerably improve the prediction performance. We anticipate that our study provides a new lead for future computational analysis of fungi phosphorylation.

PredGly: predicting lysine glycation sites for Homo sapiens based on XGboost feature optimization

Motivation

Protein glycation is a familiar post-translational modification (PTM) which is a two-step non-enzymatic reaction. Glycation not only impairs the function but also changes the characteristics of the proteins so that it is related to many human diseases. It is still much more difficult to systematically detect glycation sites due to the glycated residues without crucial patterns. Computational approaches, which can filter supposed sites prior to experimental verification, can extremely increase the efficiency of experiment work. However, the previous lysine glycation prediction method uses a small number of training datasets. Hence, the model is not generalized or pervasive.

Results

By searching from a new database, we collected a large dataset in Homo sapiens. PredGly, a novel software, can predict lysine glycation sites for H.sapiens, which was developed by combining multiple features. In addition, XGboost was adopted to optimize feature vectors and to improve the model performance. Through comparing various classifiers, support vector machine achieved an optimal performance. On the basis of a new independent test set, PredGly outperformed other glycation tools. It suggests that PredGly can provide more instructive guidance for further experimental research of lysine glycation.

Availability and implementation

https://github.com/yujialinncu/PredGly

Supplementary information

Supplementary data are available at Bioinformatics online.

[Related factors and interaction on HIV/HCV co-infection of patients access to methadone maintenance treatment]

Objective: To estimate the prevalence of HIV/HCV co-infection and explore the influence factors and their interaction on HIV/HCV co-infection of patient's access to methadone maintenance treatment (MMT). Methods: A face to face interviews were conducted among 750 patients at two MMT clinics in Guangxi Zhuang Autonomous Region. The questionnaires information included demographic characteristics, HIV and HCV infection status, history of drug abuse, urine test for morphine, high risk sex behaviors, needle sharing, dropped out etc. Methods of χ(2) test one-way, multivariate logistic regression and interactions were used to analyze the related factors of HIV/HCV co-infection. Results: The study subjects included 750 participants, 18.31% (127/691) of patients were co-infected with HIV and HCV. The HIV/HCV co-infection rate in patients who shared needles with others or dropped out of treatment was 35.84% (81/226) and 19.88% (64/322) respectively, which were higher than those who have never shared needles or dropped out (9.89%, 46/465 and 17.07%, 63/369). Logistic regression analysis results showed that after adjusted for confounding factors, patients who shared needles (OR=4.50, 95%CI: 2.72-7.43) and dropped out of treatment (OR=1.71, 95%CI: 1.04-2.80) were more likely to be infected with HIV/HCV. Interaction analysis showed that sharing needles and dropping out of treatment exist additive effect on co-infection of HIV and HCV (RERI=4.21, AP=0.44, SI=1.95). Conclusions: Needle sharing and dropping out of treatment are associated with HIV/HCV co-infection. Health education, psychological counseling and other measures should be taken to reduce needle sharing and dropping out of MMT.

Detection and perfect fitting of 13.2 dB squeezed vacuum states by considering green-light-induced infrared absorption

We report on a high-level squeezed vacuum state with maximum quantum noise reduction of 13.2 dB directly detected at the pump power of 180 mW. The pump power dependence of the squeezing factor is experimentally exhibited. When considering only loss and phase fluctuation, the fitting results have a large deviation from the measurement value near the threshold. By integrating green-light-induced infrared absorption (GLIIRA) loss, the squeezing factor can be perfectly fitted in the whole pump power range. The result indicates that GLIIRA loss should be thoroughly considered and quantified in the generation of high-level squeezed states.

SIS-ECM Laden with GMSC-Derived Exosomes Promote Taste Bud Regeneration

Oral cancer has a high annual incidence rate all over the world, and the tongue is the most frequently affected anatomic structure. The current standard care is ablative surgery of malignant neoplasm, followed by tongue reconstruction with free flap. However, such reconstructive modalities with postsurgery radiotherapy or chemotherapy can hardly support the functional recovery of the tongue-particularly, functional taste bud regeneration-in reconstructed areas, thus seriously affecting patients' prognosis and life quality. Using a critical-sized tongue defect model in rats, we show that combinatory transplantation of small intestinal submucosa-extracellular matrix (SIS-ECM) with gingival mesenchymal stem cells (GMSCs) or their derivative exosomes promoted tongue lingual papillae recovery and taste bud regeneration as evidenced by increased expression of CK14, CK8, and markers for type I, II, and III taste bud cells (NTPdase 2, PLC-β2, and AADC, respectively). In addition, our results indicate that GMSCs or their derivative exosomes could increase BDNF expression, a growth factor that plays an important role in the proliferation and differentiation of epithelial basal progenitor cells into taste bud cells. Meanwhile, we showed an elevated expression level of Shh-which is essential for development, homeostasis, and maintenance of the taste bud organ-in wounded areas of the tongue among animals treated with GMSC/SIS-ECM or exosome/SIS-ECM as compared with SIS-ECM control. Moreover, our data show that GMSCs or their derivative exosomes promoted innervation of regenerated taste buds, as evidenced by elevated expressions of neurofilament and P2X₃ at the injury areas. Together, our findings indicate that GMSC/SIS-ECM and exosome/SIS-ECM constructs can facilitate taste bud regeneration and reinnervation with promising potential application in postsurgery tongue reconstruction of patients with tongue cancer.