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Mitochondrial alternative oxidase 1a (AOX1a) plays an extremely important role in critical node of seed viability. However, the regulatory mechanism is still poorly understood. The study aims to identify regulatory mechanisms by comparing between OsAOX1a-RNAi and wild type (WT) rice seed during artificial aging treatment. Gain weight and P50 significantly decreased in OsAOX1a-RNAi rice seed, indicating that there might be impaired in seed development and storability. Compared to WT seeds in the 100%, 90%, 80%, and 70% germination, respectively, NADH and succinate-dependent O2 consumption, the activity mitochondrial malate dehydro-genase and ATP contents were decreased in OsAOX1a-RNAi seeds in the 100%, 90%, 80%, and 70% germination, respectively, indicating that mitochondrial status in the OsAOX1a-RNAi seeds after imbibition was weaken than the WT. In addition to, the reduced abundance of complex I N and P module subunits might showed that the capacity of mitochondrial electron transfer chain was significantly inhibited in the OsAOX1a-RNAi seed at critical node of seed viability. Above results might indicated that the ATP production was impaired in OsAOX1a-RNAi seeds during ageing. Therefore, we conclude that the activities of mitochondrial metabolism and alternative pathways were severely inhibited in OsAOX1a-RNAi seeds at critical node of viability, which was leading to accelerate the collapse of seed viability. The precise regulatory mechanism of the alternative pathway at the critical node of viability still needs to be further analyzed.

C46H60N6O2Se2, triclinic, P 1 ‾ $\overline{1}$ (no. 2), a = 10.4701(7) Å, b = 10.6331(7) Å, c = 20.4665(14) Å, α = 92.079(2)°, β = 97.937(2)°, γ = 95.848(2)°, V = 2242.0(3) Å3, Z = 2, R gt (F) = 0.0487, wR ref (F 2) = 0.1183, T = 293(2) K.

Background Lipoprotein-associated phospholipase A2 (Lp-PLA2) is closely related to the development of cardiovascular diseases, and the association between Lp-PLA2 and lower extremity arterial disease (LEAD) in type 2 diabetes mellitus (T2DM) is inconsistent among previous studies. Thus, the present study aimed to investigate whether the increase in Lp-PLA2 is related to the occurrence of LEAD in patients with T2DM. Methods A total of 519 patients with T2DM (173 patients with LEAD and 346 patients without LEAD) were enrolled in this study. The demographics, medical history, serum lipids, glycosylated hemoglobin, Lp-PLA2, and ankle-brachial index (ABI) were recorded and analyzed. Results The diabetes duration, prevalence of female, prevalence of hypertension, and Lp-PLA2 concentration in the LEAD group were significantly higher than those in the non-LEAD group (duration of diabetes: 15 [10–20] vs 8 [2–12] years, prevalence of female: 49.13% vs 38.73%, prevalence of hypertension: 58.38% vs 38.11%, Lp-PLA2: 145 [108–178] vs 125 [107–138] ng/ml, p Conclusions Increased serum Lp-PLA2 concentrations are associated with LEAD in patients with T2DM. They are an independent risk factor for the occurrence of LEAD.

Accumulating evidence indicates that the pluripotency of periodontal ligament stem cells (PDLSCs) is compromised under inflammatory conditions; however, the underlying mechanisms remain largely unexplored. In this study, we hypothesize that the P2X7 receptor (P2X7R) is a key molecule linked to inflammation-associated impairment of PDLSCs. We first investigated P2X7R expression in PDLSCs under normal and inflammatory conditions and then determined the effect of a P2X7R agonist (BzATP) or antagonist (BBG) on PDLSC osteogenesis under various conditions. Gene-modified PDLSCs were used to further examine the role of P2X7R and the signaling pathway underlying P2X7R-enhanced osteogenesis. We found that inflammatory conditions decreased P2X7R expression in PDLSCs and reduced osteogenesis in these cells. In addition, activation of P2X7R by BzATP or overexpression of P2X7R via gene transduction reversed the inflammation-mediated decrease in PDLSC osteogenic differentiation. When selected osteogenesis-related signaling molecules were screened, the PI3K-AKT-mTOR pathway was identified as potentially involved in P2X7R-enhanced PDLSC osteogenesis. Our data reveal a crucial role for P2X7R in PDLSC osteogenesis under inflammatory conditions, suggesting a new therapeutic target to reverse or rescue inflammation-mediated changes in PDLSCs for future mainstream therapeutic uses.

Although substantial data indicate that the osteogenic potential of periodontal ligament stem cells (PDLSCs) is compromised under inflammatory conditions, the underlying mechanism remains largely unexplored. In this study, we found that both the autophagy levels and autophagic flux levels were decreased in PDLSCs incubated under inflammatory conditions (I-PDLSCs). Based on the increased expression of LC3 II (at an autophagy level) and decreased accumulation of LC3 II (at an autophagic flux level) in I-PDLSCs, we speculated that the disruption of I-PDLSC autophagy arose from dysfunction of the cellular autophagy-lysosome system. Subsequently, our hypothesis was demonstrated by inhibited autophagosome-lysosome fusion, damaged lysosomal function, and suppressed activation of transcription factor EB (TFEB, a master regulator of the autophagy-lysosome system) in I-PDLSCs and verified by TFEB overexpression in I-PDLSCs. We found that gold nanoparticle (Au NP) treatment rescued the osteogenic potential of I-PDLSCs by restoring the inflammation-compromised autophagy-lysosome system. In this context, Au NP ceased to be effective when TFEB was knocked down in PDLSCs. Our data demonstrate the crucial role of the autophagy-lysosome system in cellular osteogenesis under inflammatory conditions and suggest a new target for rescuing inflammation-induced cell dysfunction using nanomaterials to aid cell biology and tissue regeneration.

Obesity has been believed to be closely linked with many kinds of diseases including atherosclerosis, hypertension, cerebrovascular thrombosis, and diabetes. Ghrelin and Homeobox transcript antisense RNA (HOTAIR) were believed to be involved in the regulation of myocardial injury.The obesity mice model was established through feeding mice (C57BL/6J, male, eight-week-old) with high-fat diet and palmitate (PA)-induced cardiomyocyte injury. RNA and protein levels were detected with Quantitative real-time PCR and Western blotting. The levels of TG, TCH, LDL, CK-MB, cTnl, and BNP in the serum or cell medium supernatant were measured using ELISA kits. The ROS level was detected with the DCFH-DA method. Binding sites between different targets were identified using detection of dual luciferase reporter assay. Cell apoptosis was analyzed by flow cytometry. RNA-binding protein immunoprecipitation and chromatin immunoprecipitation were used to detect the binding of DNMT3B with HOTAIR or miR-196b promoter.The expression of HOTAIR was downregulated, and miR-196b was upregulated in the obese myocardial injury. Ghrelin attenuated PA-induced cardiomyocyte injury by increasing HOTAIR. HOTAIR regulated the expression of miR-196b by recruiting DNMT3B to induce methylation of the miR-196b gene promoter. The binding site between miR-196b and IGF-1 was identified.We demonstrated that ghrelin attenuated PA-induced cardiomyocyte injury by regulating the HOTAIR/miR-196b/IGF-1 signaling pathway. Our findings might provide novel thought for the prevention and treatment of obesity-induced myocardial injury by targeting HOTAIR/miR-196b.

Background Stem cells that have undergone long-term ex vivo expansion are most likely functionally compromised (namely cellular senescence) in terms of their stem cell properties and therapeutic potential. Due to its ability to attenuate cellular senescence, melatonin (MLT) has been proposed as an adjuvant in long-term cell expansion protocols, but the mechanism underlying MLT-induced cell rejuvenation remains largely unknown. Methods Human periodontal ligament stem cells (PDLSCs) were isolated and cultured ex vivo for up to 15 passages, and cells from passages 2, 7, and 15 (P2, P7, and P15) were used to investigate cellular senescence and autophagy change in response to long-term expansion and indeed the following MLT treatment. Next, we examined whether MLT could induce cell rejuvenation by restoring the autophagic processes of damaged cells and explored the underlying signaling pathways. In this context, cellular senescence was indicated by senescence-associated β-galactosidase (SA-β-gal) activity and by the expression of senescence-related proteins, including p53, p21, p16, and γ-H2AX. In parallel, cell autophagic processes were evaluated by examining autophagic vesicles (by transmission electronic microscopy), autophagic flux (by assessing mRFP-GFP-LC3-transfected cells), and autophagy-associated proteins (by Western blot assay of Atg7, Beclin-1, LC3-II, and p62). Results We found that long-term in vitro passaging led to cell senescence along with impaired autophagy. As expected, MLT supplementation not only restored cells to a younger state but also restored autophagy in senescent cells. Additionally, we demonstrated that autophagy inhibitors could block MLT-induced cell rejuvenation. When the underlying signaling pathways involved were investigated, we found that the MLT receptor (MT) mediated MLT-related autophagy restoration by regulating the PI3K/AKT/mTOR signaling pathway. Conclusions The present study suggests that MLT may attenuate long-term expansion-caused cellular senescence by restoring autophagy, most likely via the PI3K/AKT/mTOR signaling pathway in an MT-dependent manner. This is the first report identifying the involvement of MT-dependent PI3K/AKT/mTOR signaling in MLT-induced autophagy alteration, indicating a potential of autophagy-restoring agents such as MLT to be used in the development of optimized clinical-scale cell production protocols.

Objectives Previously, our investigations demonstrated robust pro‐angiogenic potentials of extracellular vesicles secreted by periodontitis‐compromised dental pulp stem cells (P‐EVs) when compared to those from healthy DPSCs (H‐EVs), but the underlying mechanism remains unknown. Materials and methods Here, circulating microRNAs (miRNAs) specifically found in P‐EVs (compared with H‐EVs) were identified by Agilent miRNA microarray analysis, and the roles of the candidate miRNA in P‐EV‐enhanced cell angiogenesis were confirmed by cell transfection and RNA interference methods. Next, the direct binding affinity between the candidate miRNA and its target gene was evaluated by luciferase reporter assay. CCK‐8, transwell/scratch wound healing and tube formation assays were established to investigate the proliferation, migration, and tube formation abilities of endothelial cells (ECs). Western blot was employed to measure the protein levels of Hedgehog/Gli1 signalling pathway components and angiogenesis‐related factors. Results The angiogenesis‐related miRNA miR‐378a was found to be enriched in P‐EVs, and its role in P‐EV‐enhanced cell angiogenesis was confirmed, wherein Sufu was identified as a downstream target gene of miR‐378a. Functionally, silencing of Sufu stimulated EC proliferation, migration and tube formation by activating Hedgehog/Gli1 signalling. Further, we found that incubation with P‐EVs enabled the transmission of P‐EV‐contained miR‐378a to ECs. Subsequently, the expressions of Sufu, Gli1 and vascular endothelial growth factor in ECs were significantly influenced by P‐EV‐mediated miR‐378a transmission. Conclusions These data suggest that P‐EVs carrying miR‐378a promote EC angiogenesis by downregulating Sufu to activate the Hedgehog/Gli1 signalling pathway. Our findings reveal a crucial role for EV‐derived miR‐378a in cell angiogenesis and hence offer a new target for modifying stem cells and their secreted EVs to enhance vessel regenerative potential., P‐EVs carrying miR‐378a promote the angiogenesis of ECs by down‐regulating Sufu to activate the Hedgehog/Gli1 signalling pathway.

Background: Stem cells undergone long-term ex-vivo expansion are most likely functionally compromised (namely cellular senescence) in terms of their stem cell properties and therapeutic potentials. Due to the ability to attenuate cellular senescence, melatonin (MLT) has been proposed as an adjuvant across long-term cell expansion protocols, but the underlying mechanism remains largely unknown. Methods: Human periodontal ligament stem cells (PDLSCs) were isolated and cultured ex-vivo for 15 passages, and passage 2, 7 and 15 cells were used to interrogate the cellular senescence and alteration in cell autophagy during long-term expansion. The cellular senescence features were evidenced by senescence-associated β-galacotosidase (SA-β-gal) activity and the expression of senescence-related proteins including p53, p21, p16 and γ-H2AX. Electronic microscope was used to observe the autophagic vesicles. Adenovirus mRFP-GFP-LC3 was transfected to indicate the alteration of autophagic flux during long-term expansion, and the autophagy-associated proteins Atg7, Beclin-1, LC3-II and p62 were evaluated by Western blot. Results: It was found that long-term in-vitro passaging led to an accumulated SA-β-gal, elevated expressions of p53, p21, p16 and γ-H2AX, along with downregulated autophagy-associated proteins Atg7, Beclin-1 and LC3 as well as a mounting autophagy substrate p62. In accordance with expectation, supplemented with MLT not only ameliorated cells to a younger state but also restored the impaired autophagy level in senescent cells. Additionally, we demonstrated that autophagy inhibitor could block such MLT-induced cell rejuvenation. When the underlying signaling pathways involved was interrogated, we found that MLT receptor (MT) participated in mediating MLT-related autophagy restoration by regulating PI3K/AKT/mTOR signaling pathway.Conclusions: The present study suggests that MLT may rejuvenate long-term expansion-caused cellular senescence by restoring autophagy, more likely via PI3K/AKT/mTOR signaling pathway in an MT-dependent manner. This is the first report identifying the MT-dependent PI3K/AKT/mTOR signaling involved in MLT-induced autophagy alteration, pointing to a potential target for using autophagy-restoring agents such as MLT to develop optimized clinical-scale cell production protocols.

Lipoprotein-associated phospholipase AA total of 519 patients with T2DM (173 patients with LEAD and 346 patients without LEAD) were enrolled in this study. The demographics, medical history, serum lipids, glycosylated hemoglobin, Lp-PLAThe diabetes duration, prevalence of female, prevalence of hypertension, and Lp-PLAIncreased serum Lp-PLA

Periodontitis is a widespread disease characterized by inflammation-induced progressive damage to the tooth-supporting structures until tooth loss occurs. The regeneration of lost/damaged support tissue in the periodontium, including the alveolar bone, periodontal ligament, and cementum, is an ambitious purpose of periodontal regenerative therapy and might effectively reduce periodontitis-caused tooth loss. The use of stem cells for periodontal regeneration is a hot field in translational research and an emerging potential treatment for periodontitis. This concise review summarizes the regenerative approaches using either culture-expanded or host-mobilized stem cells that are currently being investigated in the laboratory and with preclinical models for periodontal tissue regeneration and highlights the most recent evidence supporting their translational potential toward a widespread use in the clinic for combating highly prevalent periodontal disease. We conclude that in addition to in vitro cell-biomaterial design and transplantation, the engineering of biomaterial devices to encourage the innate regenerative capabilities of the periodontium warrants further investigation. In comparison to cell-based therapies, the use of biomaterials is comparatively simple and sufficiently reliable to support high levels of endogenous tissue regeneration. Thus, endogenous regenerative technology is a more economical and effective as well as safer method for the treatment of clinical patients. Stem Cells Translational Medicine 2019;8:392–403

Over the past two decades, an accumulating body of evidence indicates that well-designed biomaterials are able to coax the homing of resident stem cells to injured sites and orchestrate their behaviors and functions to promote tissue regeneration. This paradigm opens a new research avenue, termed endogenous regenerative medicine (ERM) in this manuscript, that takes advantage of the body's own regenerative capacity to manage a broad spectrum of ischemic and degenerative diseases. By building on the hidden regenerative potential of resident stem cells, ERM circumvents the complex processes involved in tissue engineering and thereby facilitates the development of clinically translatable regenerative approaches. In fact, tremendous progress has been achieved in the field of ERM, and a large body of literature covering both biological discoveries made in the laboratory and preclinical successes in animal models supports the notion that ERM technologies should be translated to clinical scenarios aimed at curing disease states. In this manuscript, we summarize the strategies with either demonstrated effectiveness or significant potential for harnessing stem cell homing in therapeutics with the aims of defining new criteria for biomaterial design in the field of ERM and predicting future developments in this ever-evolving and rapidly advancing arena.

Although cellular therapy has been proposed for inflammation‐related disorders such as periodontitis for decades, clinical application has been unsuccessful. One explanation for these disappointing results is that the functions of stem cells are substantially compromised when they are transplanted into an inflammatory in vivo milieu. Considering the previous finding that P2X7 receptor (P2X7R) gene modification is able to reverse inflammation‐mediated impairment of periodontal ligament stem cells (PDLSCs), we further hypothesized that cells subjected to P2X7R gene transduction also exert influences on other cells within an in vivo milieu via an exosome‐mediated paracrine mechanism. To define the paracrine ability of P2X7R gene‐modified cells, P2X7R gene‐modified stem cell‐derived conditional medium (CM‐Ad‐P2X7) and exosomes (Exs‐Ad‐P2X7) were used to incubate PDLSCs. In an inflammatory osteogenic microenvironment, inflammation‐mediated changes in PDLSCs were substantially reduced, as shown by quantitative real‐time PCR (qRT‐PCR) analysis, Western blot analysis, alkaline phosphatase (ALP) staining/activity assays, and Alizarin red staining. In addition, the Agilent miRNA microarray system combined with qRT‐PCR analysis revealed that miR‐3679‐5p, miR‐6515‐5p, and miR‐6747‐5p were highly expressed in Exs‐Ad‐P2X7. Further functional tests and luciferase reporter assays revealed that miR‐3679‐5p and miR‐6747‐5p bound directly to the GREM‐1 protein, while miR‐6515‐5p bound to the GREM‐1 protein indirectly; these effects combined to rescue inflammation‐compromised PDLSCs from dysfunction. Thus, in addition to maintaining their robust functionality under inflammatory conditions, P2X7R gene‐modified stem cells may exert positive influences on their neighbors via a paracrine mechanism, pointing to a novel strategy for modifying the harsh local microenvironment to accommodate stem cells and promote improved tissue regeneration., The potential mechanism involved in P2X7R‐mediated rescue of inflammation‐compromised periodontal ligament stem cells from dysfunction.

Although titanium implants have been applied in dental clinics to replace lost teeth and to restore masticatory function for decades, strategies to design the surface of the transmucosal sites of implants to achieve ideal and predictable biological sealing following implantation remain to be optimized. In this study, we hypothesized that gingival epithelial cell (GEC) adhesion and new tissue attachment to titanium sheets/implants could be promoted by the release of plasmid pLAMA3-CM (encoding a motif of the C-terminal globular domain of LAMA3) from a titanium surface. To test this hypothesis, a chitosan/collagen (Chi/Col) coating was immobilized on the surfaces of titanium substrates with nanotube topography (NT-Ti) through cathodic electrophoretic deposition; it was found that pLAMA3-CM could be released from the coating in a highly sustained manner. After culturing on titanium with nanotube topography coated by Chi/Col with the plasmid pLAMA3-CM (Chi/Col/pLAMA3-CM-Ti), human GECs (hGECs) were found to effectively uptake the incorporated plasmids, which resulted in improved attachment, as evidenced by morphological and immunofluorescence analyses. In addition, Chi/Col/pLAMA3-CM-Ti induced better biological sealing at transmucosal sites following immediate implantation into Sprague-Dawley rats. Our findings indicate that the modification of titanium implants by plasmid-mediated pLAMA3-CM gene transfection points to a practical strategy for optimizing biological sealing around the transmucosal sites of implants.

The cover image is based on the Review Article L‐type voltage‐gated calcium channels in stem cells and tissue engineering by Yi‐zhou Tan et al., https://doi.org/10.1111/cpr.12623. [Image: see text]

L‐type voltage‐gated calcium ion channels (L‐VGCCs) have been demonstrated to be the mediator of several significant intracellular activities in excitable cells, such as neurons, chromaffin cells and myocytes. Recently, an increasing number of studies have investigated the function of L‐VGCCs in non‐excitable cells, particularly stem cells. However, there appear to be no systematic reviews of the relationship between L‐VGCCs and stem cells, and filling this gap is prescient considering the contribution of L‐VGCCs to the proliferation and differentiation of several types of stem cells. This review will discuss the possible involvement of L‐VGCCs in stem cells, mainly focusing on osteogenesis mediated by mesenchymal stem cells (MSCs) from different tissues and neurogenesis mediated by neural stem/progenitor cells (NSCs). Additionally, advanced applications that use these channels as the target for tissue engineering, which may offer the hope of tissue regeneration in the future, will also be explored.

Although macrophage (Mφ) polarization has been demonstrated to play crucial roles in cellular osteogenesis across the cascade of events in periodontal regeneration, how polarized Mφ phenotypes influence the cementoblastic differentiation of periodontal ligament stem cells (PDLSCs) remains unknown. In the present study, human monocyte leukemic cells (THP-1) were induced into M0, M1, and M2 subsets, and the influences of these polarized Mφs on the cementoblastic differentiation of PDLSCs were assessed in both conditioned medium-based and Transwell-based coculture systems. Furthermore, the potential pathways and cyto-/chemokines involved in Mφ-mediated cementoblastic differentiation were screened and identified. In both systems, M2 subsets increased cementoblastic differentiation-related gene/protein expression levels in cocultured PDLSCs, induced more PDLSCs to differentiate into polygonal and square cells, and enhanced alkaline phosphatase activity in PDLSCs. Furthermore, Akt and c-Jun N-terminal Kinase (JNK) signaling was identified as a potential pathway involved in M2 Mφ-enhanced PDLSC cementoblastic differentiation, and cyto-/chemokines (interleukin (IL)-10 and vascular endothelial growth factor [VEGF]) secreted by M2 Mφs were found to be key players that promoted cell cementoblastic differentiation by activating Akt signaling. Our data indicate for the first time that Mφs are key modulators during PDLSC cementoblastic differentiation and are hence very important for the regeneration of multiple periodontal tissues, including the cementum. Although the Akt and JNK pathways are involved in M2 Mφ-enhanced cementoblastic differentiation, only the Akt pathway can be activated via a cyto-/chemokine-associated mechanism, suggesting that players other than cyto-/chemokines also participate in the M2-mediated cementoblastic differentiation of PDLSCs. Stem Cells 2019;37:1567–1580

Increasing evidence indicates that material pore size can affect both macrophage (Mφ) polarization and new vessel formation within the compartment of a transplant. Using genipin cross-linked collagen/chitosan (Col-Ch) scaffolds with average pore sizes of 160 and 360 μm (Col-Ch-160 and Col-Ch-360, respectively) as material vascularization models, this study examined the influence of pore size-mediated M1-to-M2 transition of Mφs penetrating the scaffold on subsequent angiogenesis and vascularization. Following seeding in scaffolds, Mφs (M0 or M1) on both scaffolds tended to exhibit the M1 phenotype at day 1 and the M2 phenotype at day 3 and day 7. Col-Ch-360 exhibited a greater potential to encourage M1-to-M2 transition and to promote Mφ secretion of anti-inflammatory and pro-angiogenic cytokines. When supernatants derived from Mφ-scaffold cultures were used to incubate human umbilical vein endothelial cells (HUVECs), cells incubated with Col-Ch-360-derived supernatants displayed a great angiogenic response in terms of tube formation and cell migration. Compared with Col-Ch-160, subcutaneous transplantation of Col-Ch-360 scaffolds resulted in more blood vessel formation, along with more VEGF+ cells and fewer pro-inflammatory (M1) Mφs across the pores of the material. Our data suggest that compared to Col-Ch-160, Col-Ch-360 scaffolds promote angiogenesis in vitro and vascularization in vivo, most likely because Mφs residing in materials with larger pores undergo a higher degree of M1-to-M2 transition.

C10H24Ag2N2O10S2, triclinic, P1̄ (no. 2), a = 6.9547(9) Å, b = 8.4684(12) Å, c = 8.9563(15) Å, α = 117.888(15)°, β = 101.740(13)°, γ = 93.026(11)°, V = 449.75(13) Å3, Z = 1, R gt(F) = 0.0365, wR ref(F 2) = 0.0858, T = 293(2) K.

Macrophages (Mφs) are involved in a variety of physiological and pathological events including wound healing and tissue regeneration, in which they play both positive and negative roles depending on their polarization state. In this study, we investigated the cellular behaviours of bone marrow mesenchymal stem cells (BMMSCs) after incubation in different conditioned media (CMs) generated by unpolarized Mφs (M0) or polarized Mφs (M1 and M2). Mφ polarization was induced by stimulation with various cytokines, and CMs were obtained from in vitro Mφ cultures termed CM0, CM1 and CM2 based on each Mφ phenotype. We found that CM1 supported the proliferation and adipogenic differentiation of BMMSCs, whereas CM0 had a remarkable effect on cell osteogenic differentiation. To a certain degree, CM2 also facilitated BMMSC osteogenesis; in particular, cells incubated with CM2 exhibited an enhanced capacity to form robust stem cell sheets. Although incubation with CM1 also increased production of extracellular matrix components, such as fibronectin, COL‐1 and integrin β1during sheet induction, the sheets generated by CM2‐incubated cells were thicker than those generated by CM1‐incubated cells (P < 0.001). Our data suggest that each Mφ phenotype has a unique effect on BMMSCs. Fine‐tuning Mφ polarization following transplantation may serve as an effective method to modulate the therapeutic potential of BMMSCs.

Accumulating evidence indicates that the physicochemical properties of biomaterials exert profound influences on stem cell fate decisions. However, matrix-based regulation selected through in vitro analyses based on a given cell population do not genuinely reflect the in vivo conditions, in which multiple cell types are involved and interact dynamically. This study constitutes the first investigation of how macrophages (Mφs) in stiffness-tunable transglutaminase cross-linked gelatin (TG-gel) affect the osteogenesis of bone marrow-derived mesenchymal stem cells (BMMSCs). When a single cell type was cultured, low-stiffness TG-gels promoted BMMSC proliferation, whereas high-stiffness TG-gels supported cell osteogenic differentiation. However, Mφs in high-stiffness TG-gels were more likely to polarize toward the pro-inflammatory M1 phenotype. Using either conditioned medium (CM)-based incubation or Transwell-based co-culture, we found that Mφs encapsulated in the low-stiffness matrix exerted a positive effect on the osteogenesis of co-cultured BMMSCs. Conversely, Mφs in high-stiffness TG-gels negatively affected cell osteogenic differentiation. When both cell types were cultured in the same TG-gel type and placed into the Transwell system, the stiffness-related influences of Mφs on BMMSCs were significantly altered; both the low- and high-stiffness matrix induced similar levels of BMMSC osteogenesis. Although the best material parameter for synergistically affecting Mφs and BMMSCs remains unknown, our data suggest that Mφ involvement in the co-culture system alters previously identified material-related influences on BMMSCs, such as matrix stiffness-related effects, which were identified based on a culture system involving a single cell type. Such Mφ-stem cell interactions should be considered when establishing proper matrix parameter-associated cell regulation in the development of biomimetic biomaterials for regenerative applications. Statement of Significance The substrate stiffness of a scaffold plays critical roles in modulating both reparative cells, such as mesenchymal stem cells (MSCs), and immune cells, such as macrophages (Mφs). Although the influences of material stiffness on either Mφs or MSCs, have been extensively described, how the two cell types respond to matrix cues to dynamically affect each other in a three-dimensional (3D) biosystem remains largely unknown. Here, we report our findings that, in a platform wherein Mφs and bone marrow-derived MSCs coexist, matrix stiffness can influence stem cell fate through both direct matrix-associated regulation and indirect Mφ-based modulation. Our data support future studies of the MSC-Mφ-matrix interplay in the 3D context to optimize matrix parameters for the development of the next biomaterial.

The IEEE802.11 protocol proposed the CSMA/CA mechanism [1] which is more adjustable to the application of the wireless channel based on CSMA. This article will analyze the property of the traffic in the multi-hop wireless network, give the definitions and the migration relationship of four channel states, provide a model for the traffic of the nodes and describe the relationship among the part of the parameters based on the IEEE802.11 protocol.

The thesis research aimed to further the study of human-robot interaction (HRI) issues, especially regarding the development of rescue robot. The paper firstly discussed the status of the rescue robot and described the framework of human-robot interaction of search-rescue robot and rescue-evacuation robot. Subsequently, the general HRI issues will be discussed to explain how they affect the use of robots. Finally, we present suggested this multidisciplinary field of research, namely human-robot interaction, requires contributions from a variety of research fields such as robotics, human-computer interaction, and artificial intelligence.

This study tested whether activation of adrenoreceptors in chondrocytes has roles in degenerative remodelling of temporomandibular joint (TMJ) and to determine associated mechanisms. Unilateral anterior crossbite (UAC) was established to induce TMJ degeneration in rats. Saline vehicle, α2- and β-adrenoreceptor antagonists or agonists were injected locally into the TMJ area of UAC rats. Cartilage degeneration, subchondral bone microarchitecture and the expression of adrenoreceptors, aggrecans, matrix metalloproteinases (MMPs) and RANKL by chondrocytes were evaluated. Chondrocytes were stimulated by norepinephrine to investigate signal transduction of adrenoreceptors. Increased α2A-adrenoreceptor expression was observed in condylar cartilage of UAC rats, together with cartilage degeneration and subchondral bone loss. Norepinephrine depresses aggrecans expression but stimulates MMP-3, MMP-13 and RANKL production by chondrocytes through ERK1/2 and PKA pathway; these effects were abolished by an α2A-adrenoreceptor antagonist. Furthermore, inhibition of α2A-adrenoreceptor attenuated degenerative remodelling in the condylar cartilage and subchondral bone, as revealed by increased cartilage thickness, proteoglycans and aggrecan expression and decreased MMP-3, MMP-13 and RANKL expressions in cartilage, increased BMD, BV/TV and decreased Tb.Sp in subchondral bone. Conversely, activation of α2A-adrenoreceptor intensified aforementioned degenerative changes in UAC rats. It is concluded that activation of α2A-adrenergic signal in chondrocytes promotes TMJ degenerative remodelling by chondrocyte-mediated pro-catabolic activities.

Each year, according to Chinese and European statistics, there are many serious injuries and even fatalities of travelers into subway transit stations. Consequently, it becomes more and more important for transit authorities to evaluate these facilities (platform, gates, stairs, escalators, etc.) under critical traffic conditions, such as rush hours or emergency situations. The purpose of this paper is to review existing research results, develop the main Framework of station capacity assessment and finally point out the key issues of subway station capacity assessment.

Cleidocranial dysplasia (CCD) is an autosomal-dominant inheritable disease which is secondary to haploinsufficiency of the transcription factor runt-related transcription factor 2 (RUNX2). During the past 10 years, additional cases of RUNX2 mutation have been identified in nearly 500 families with CCD, including familial and sporadic cases (Otto et al. 2002). Some degree of clavicular hypoplasia is the most consistent feature of the disease and is often opposed at the mid line (Tang et al. 2007), while complete absence is rare and complicated to explain the specific mechanism. RUNX2, which is mapped to chromosome 6p21, was identified as the CCD causative gene in 1997 (Mundlos et al. 1997). This gene is the key transcription factor for osteoblastic differentiation, chondrocyte maturation and skeletal morphogenesis (Komori et al. 1997). Moreover, stability of RUNX2 protein, regulated by CBFb, is required for skeletal development by regulating chondrocyte differentiation, proliferation and osteoblast differentiation (Qin et al. 2014). RUNX2-deficient mice displayed impaired bone development manifestation as wide sutures, decreased bone ossification and hypoplastic clavicles (Kundu et al. 2002). RUNX2 consists of eight coding exons and spans a genomic region of 130 kb. According to the analysis of the protein structure, RUNX2 has several functional domains: QA domain, runt domain, nuclear localization signal (NSL), PST domain, VWRPY and nuclear matrix targeting sequence (NMTS). The QA domain, a stretch of 23 polyglutamine and 17 polyalanine tracts, is located in the N-terminus of RUNX2. An in vitro mutagenesis study showed that the QA domain prevented CBFb from binding to RUNX2. Deletionof the QA domain resulted in a four-fold decrease

Biomaterials that exhibit bioinspired behavior enable a range of novel biomedical applications. Cell-friendly biomaterials incorporating crucial physicochemical cues can instruct and dictate cell behavior both in vitro and in vivo. Despite substantial advances, engineering a complex cell regulatory system that incorporates mechanical and chemical signals targeting specific intracellular events has remained far from a reality. Recently, biological studies have begun to decipher the dynamic interplay between stem cells and their microenvironments. Moreover, the myriad recently developed advanced material biotechnologies, such as 3D bioprinting, protein engineering, release technology, high-throughput screening, and microfluidics, have enabled the engineering of sophisticated biomaterial systems that increasingly closely mimic the spatial and temporal characteristics of the native cell milieu. Thus, biomaterials engineered in the laboratory not only provide a fertile environment for fostering stem cells but also exhibit properties that elicit favorable crosstalk between the structural components, the cells and the host tissue in a precise physiological manner, enabling balanced matrix generation and degradation for successful tissue regeneration to be achieved. This progress report discusses these advanced biotechnologies for the design, fabrication, and functionalization of biomaterials, highlighting their merits over traditional methodologies for mimicking the structural and mechanical properties of their natural in vivo counterparts.

Isolation, structure determination and cytotoxicity of five novel triterpenes, gypensapogenins A—D, (I)—(IIb), as well as glucopyranoside of gypensapogenin D (IIc), are described.

Five novel triterpenes were isolated from hydrolyzate of total saponins from Gynostemma pentaphyllum and identified as gypensapogenin A (1), gypensapogenin B (2), gypensapogenin C (3), 3-O-β- d -glucopyranosyl-gypensapogenin D (4) and gypensapogenin D (5), two of which (1 and 2) possess unprecedented ring A. The cyclization of the side chains-3 formed five-membered cyclic ketone rings similar to ring E in 1. The 21-oic acid-21, 23-lactone was present in the side chains of 4 and 5. We also proposed the possible formation mechanisms of compounds 1–3. Compounds 1–5 were evaluated for cytotoxic activities in three cell lines including A549, U87 and Hep3B and compound 3 showed significant activities toward A549 and U87 human cancer cells (with IC 50 values at 0.11 and 0.58 μm respectively).