A new family of proteins is required for tethering of Casparian strip membrane domain and nutrient homoeostasis in rice.

Cell-cell junctions are essential for multicellular organisms to maintain nutrient homoeostasis. A plant-type tight junction, the Casparian strip (CS)-Casparian strip membrane domain (CSD) that seals the paracellular space between adjacent endodermal cells, has been known for more than one hundred years. However, the molecular basis of this structure remains unknown. Here we report that a new family of proteins containing a glycine/alanine/proline-rich domain, a lectin domain and a secretory signal peptide (GAPLESS) mediates tethering of the plasma membrane to the CS in rice. The GAPLESS proteins are specifically localized in the CS of root endodermal cells, and loss of their functions results in a disabled cell-cell junction and disrupted nutrient homoeostasis. The GAPLESS protein forms a tight complex with OsCASP1 in the plasma membrane, thereby mediating the CS-CSD junction. This study provides valuable insights into the junctional complex of plant endodermal cells, shedding light on our understanding of nutrient homoeostasis in crops and the cell junctions of eukaryotes.

The OsNAC24-OsNAP protein complex activates OsGBSSI and OsSBEI expression to fine-tune starch biosynthesis in rice endosperm.

Starch accounts for up to 90% of the dry weight of rice endosperm and is a key determinant of grain quality. Although starch biosynthesis enzymes have been comprehensively studied, transcriptional regulation of starch-synthesis enzyme-coding genes (SECGs) is largely unknown. In this study, we explored the role of a NAC transcription factor, OsNAC24, in regulating starch biosynthesis in rice. OsNAC24 is highly expressed in developing endosperm. The endosperm of osnac24 mutants is normal in appearance as is starch granule morphology, while total starch content, amylose content, chain length distribution of amylopectin and the physicochemical properties of the starch are changed. In addition, the expression of several SECGs was altered in osnac24 mutant plants. OsNAC24 is a transcriptional activator that targets the promoters of six SECGs; OsGBSSI, OsSBEI, OsAGPS2, OsSSI, OsSSIIIa and OsSSIVb. Since both the mRNA and protein abundances of OsGBSSI and OsSBEI were decreased in the mutants, OsNAC24 functions to regulate starch synthesis mainly through OsGBSSI and OsSBEI. Furthermore, OsNAC24 binds to the newly identified motifs TTGACAA, AGAAGA and ACAAGA as well as the core NAC-binding motif CACG. Another NAC family member, OsNAP, interacts with OsNAC24 and coactivates target gene expression. Loss-of-function of OsNAP led to altered expression in all tested SECGs and reduced the starch content. These results demonstrate that the OsNAC24-OsNAP complex plays key roles in fine-tuning starch synthesis in rice endosperm and further suggest that manipulating the OsNAC24-OsNAP complex regulatory network could be a potential strategy for breeding rice cultivars with improved cooking and eating quality.

CircLASP1 silence strengthens the therapeutic effects of MK-2206 on nasopharyngeal cancer through upregulating miR-625.

Therapeutic effects of MK-2206 are largely limited due to the complexity of the pathogenesis of nasopharyngeal cancer (NPC). Here, we aimed to investigate whether and how circLASP1 is involved in the therapeutic effects of MK-2206 on NPC. We showed circLASP1 was increased while miR-625 was decreased in NPC tissues and cell lines. CircLASP1 silence strengthened the therapeutic effects of MK-2206 via suppressing NPC cell proliferation and inducing autophagy and apoptosis in vitro. In mechanism analyses, we found that circLASP1 indirectly released AKT by directly binding to miR-625 in NPC cells, and miR-625 acted as a tumor suppressor in NPC and activated cell autophagy through inhibiting the AKT/mTOR pathway. Most importantly, knockdown of circLASP1 was revealed to enhance the therapeutic effects of MK-2206 on NPC in vivo. Our results suggest that the circLASP1/miR-625 axis is involved the therapeutic effects of MK-2206 on NPC by regulating autophagy, proliferation, and apoptosis through the AKT/mTOR pathway. miR-625 is involved in NPC tumorigenesis.

Multiple variation patterns of terpene synthases in 26 maize genomes.

Terpenoids are important compounds associated with the pest and herbivore resistance mechanisms of plants; consequently, it is essential to identify and explore terpene synthase (TPS) genes in maize. In the present study, we identified 31 TPS genes based on a pan-genome of 26 high-quality maize genomes containing 20 core genes (present in all 26 lines), seven dispensable genes (present in 2 to 23 lines), three near-core genes (present in 24 to 25 lines), and one private gene (present in only 1 line). Evaluation of ka/ks values of TPS in 26 varieties revealed that TPS25 was subjected to positive selection in some varieties. Six ZmTPS had ka/ks values less than 1, indicating that they were subjected to purifying selection. In 26 genomes, significant differences were observed in ZmTPS25 expression between genes affected by structural variation (SV) and those not affected by SV. In some varieties, SV altered the conserved structural domains resulting in a considerable number of atypical genes. The analysis of RNA-seq data of maize Ostrinia furnacalis feeding revealed 10 differentially expressed ZmTPS, 9 of which were core genes. However, many atypical genes for these responsive genes were identified in several genomes. These findings provide a novel resource for functional studies of ZmTPS.

The impacts of fermented feed on laying performance, egg quality, immune function, intestinal morphology and microbiota of laying hens in the late laying cycle.

Fermented feed has the potential to improve poultry gastrointestinal microecological environment, health condition and production performance. Thus, the present study was undertaken to explore the effects of fermented feed on the laying performance, egg quality, immune function, intestinal morphology and microbiota of laying hens in the late laying cycle. A total of 360 healthy Hy-Line Brown laying hens aged 80 weeks were used to conduct a 56-day study. All hens were randomly separated into two treatment groups, with five replicates of 36 hens each as follows: basal diet containing 0.0% fermented feed (CON) and 20% fermented feed (FF). Subsequent analyses revealed that fermented feed supplementation was associated with significant increases in laying rates together with reduced broken egg rates and feed conversion ratio for hens in FF group (P < 0.05). There were additionally significant increases in both albumen height and Haugh unit values in hens following fermented feed supplementation (P < 0.05). Fermented feed was also associated with increases in duodenal, jejunal and ileac villus height (P < 0.05). Laying hens fed fermented feed had higher immune globulin (Ig)A, IgG, IgM levels (P < 0.01,) and higher interleukin 2, interleukin 6, tumour necrosis factor α and interferon γ (P < 0.05) concentrations than CON. Analysis of the microbiota in these laying hens revealed the alpha diversity was not significantly affected by fermented feed supplementation. Firmicutes abundance was reduced in caecal samples from FF hens relative to those from CON hens (30.61 vs 35.12%, P < 0.05). At the genus level, fermented feed was associated with improvements in relative Lactobacillus, Megasphaera and Peptococcus abundance and decreased Campylobacter abundance in laying hens. These results suggest that fermented feed supplementation may be beneficial to the laying performance, egg quality, immunological function, intestinal villus growth and caecal microecological environment of laying hens at the end of the laying cycle.

OsNAC129 Regulates Seed Development and Plant Growth and Participates in the Brassinosteroid Signaling Pathway.

Grain size and the endosperm starch content determine grain yield and quality in rice. Although these yield components have been intensively studied, their regulatory mechanisms are still largely unknown. In this study, we show that loss-of-function of OsNAC129, a member of the NAC transcription factor gene family that has its highest expression in the immature seed, greatly increased grain length, grain weight, apparent amylose content (AAC), and plant height. Overexpression of OsNAC129 had the opposite effect, significantly decreasing grain width, grain weight, AAC, and plant height. Cytological observation of the outer epidermal cells of the lemma using a scanning electron microscope (SEM) revealed that increased grain length in the osnac129 mutant was due to increased cell length compared with wild-type (WT) plants. The expression of OsPGL1 and OsPGL2, two positive grain-size regulators that control cell elongation, was consistently upregulated in osnac129 mutant plants but downregulated in OsNAC129 overexpression plants. Furthermore, we also found that several starch synthase-encoding genes, including OsGBSSI, were upregulated in the osnac129 mutant and downregulated in the overexpression plants compared with WT plants, implying a negative regulatory role for OsNAC129 both in grain size and starch biosynthesis. Additionally, we found that the expression of OsNAC129 was induced exclusively by abscisic acid (ABA) in seedlings, but OsNAC129-overexpressing plants displayed reduced sensitivity to exogenous brassinolide (BR). Therefore, the results of our study demonstrate that OsNAC129 negatively regulates seed development and plant growth, and further suggest that OsNAC129 participates in the BR signaling pathway.

Glycogen synthase kinase 3 beta inhibitor SB216763 improves Kir2.1 expression after myocardia infraction in rats.

BACKGROUND: Abnormal ion channel currents caused by myocardial electrical remodeling is one of the main causes of malignant arrhythmias. Glycogen synthase kinase 3ß (GSK-3ß) is the main therapeutic target following ischemia as it regulates nerve cell channels. However, few studies have investigated its role in myocardial electrical remodeling. The present study aimed to investigate the role of GSK-3ß in a rat myocardial infarction (MI)-induced electrical remodeling and potential effects on cardiac ionic channels including KCNJ2/Kir2.1/IK1. METHODS: Ligation of the left anterior descending artery in rats was performed to establish a MI model. The rats were randomly divided into three groups, the sham, MI, and MI + SB group. The animals in the latter group were administered SB216763 (GSK-3ß inhibitor) at a dose of 0.6 mg·kg-1·day-1. The ventricular function was assessed by echocardiography, electrocardiography, and histological analysis 7 days post-surgery. Serum was collected to measure lactate dehydrogenase and cardiac troponin I levels, and the mRNA and protein levels of the KCNJ2/Kir2.1/IK1 channel in the heart tissues were assessed. H9c2 cells were cultured to examine the effects of SB216763 on the protein expression of Kir2.1 channel under hypoxic conditions. RESULTS: The results revealed that SB216763 ameliorated acute cardiac injury and improved myocardial dysfunction. Moreover, SB216763 increased the mRNA and protein expression of Kir2.1 during MI. Furthermore, SB216763 treatment abrogated the decreased expression of Kir2.1 in H9c2 cells under hypoxic conditions. CONCLUSIONS: GSK-3ß inhibition upregulates Kir2.1 expression in a rat model of MI.

High-resolution quantitative trait locus mapping for rice grain quality traits using genotyping by sequencing.

Rice is a major food crop that sustains approximately half of the world population. Recent worldwide improvements in the standard of living have increased the demand for high-quality rice. Accurate identification of quantitative trait loci (QTLs) for rice grain quality traits will facilitate rice quality breeding and improvement. In the present study, we performed high-resolution QTL mapping for rice grain quality traits using a genotyping-by-sequencing approach. An F2 population derived from a cross between an elite japonica variety, Koshihikari, and an indica variety, Nona Bokra, was used to construct a high-density genetic map. A total of 3,830 single nucleotide polymorphism markers were mapped to 12 linkage groups spanning a total length of 2,456.4 cM, with an average genetic distance of 0.82 cM. Seven grain quality traits-the percentage of whole grain, percentage of head rice, percentage of area of head rice, transparency, percentage of chalky rice, percentage of chalkiness area, and degree of chalkiness-of the F2 population were investigated. In total, 15 QTLs with logarithm of the odds (LOD) scores >4 were identified, which mapped to chromosomes 6, 7, and 9. These loci include four QTLs for transparency, four for percentage of chalky rice, four for percentage of chalkiness area, and three for degree of chalkiness, accounting for 0.01%-61.64% of the total phenotypic variation. Of these QTLs, only one overlapped with previously reported QTLs, and the others were novel. By comparing the major QTL regions in the rice genome, several key candidate genes reported to play crucial roles in grain quality traits were identified. These findings will expedite the fine mapping of these QTLs and QTL pyramiding, which will facilitate the genetic improvement of rice grain quality.

Risk factors of continuous renal replacement therapy following total aortic arch replacement under moderate hypothermia.

BACKGROUND: Stanford type A aortic dissection (TAAD) has a sudden onset and high mortality, and emergency total aortic arch replacement (TAAR) is the main treatment option for TAAD. The mortality rate of patients with postoperative acute kidney injury (AKI) combined with continuous renal replacement therapy (CRRT) is remarkable higher than that of patients without AKI. However, incidence of AKI and risk factors for CRRT following TAAR isn't entirely understood. METHODS: From October 2018 to March 2021, all patients with Stanford type A dissection who underwent total arch replacement surgery under MHCA were enrolled. According to whether CRRT treatment was performed, participants were divided into a CRRT group (n=49) and control group (n=72). Both groups incorporated the brain protection strategy of moderate hypothermia, and the left common carotid artery and the innominate artery were perfused anteriorly. Relevant medical data was collected. RESULTS: Age, gender, and a history of smoking and drinking were not significantly different between the 2 groups (P>0.1). There were statistical differences between the 2 groups in aortic sinus diameter and Bentall procedure (P≤0.05). Univariate analysis revealed that fresh frozen plasma was a protective factor (P<0.05) and the intraoperative transfusion volume of red blood cells, platelets, fresh frozen plasma, autologous blood used for intraoperative bleeding, aortic sinus diameter, and Bentall procedure were risk factors (P<0.1). Multivariate analysis showed that the Bentall procedure and intraoperative bleeding were risk factors for CRRT (P<0.05), and the aortic sinus diameter and intraoperative transfusion score were also risk factors for CRRT (P<0.05). Receiver operating characteristic (ROC) analysis demonstrated that the model of aortic sinus diameter and intraoperative transfusion score had more significantly different discriminatory powers. CONCLUSIONS: The Bentall procedure, intraoperative bleeding, aortic sinus diameter, and intraoperative transfusion score were risk factors for postoperative CRRT. The model of aortic sinus diameter and intraoperative transfusion score had more significantly different discriminatory powers.

Targeting Glycogen Synthase Kinase 3 Beta Regulates CD47 Expression After Myocardial Infarction in Rats via the NF-κB Signaling Pathway.

The aim of this study was to investigate the effects of the GSK-3ß/NF-κB pathway on integrin-associated protein (CD47) expression after myocardial infarction (MI) in rats. An MI Sprague Dawley rat model was established by ligating the left anterior descending coronary artery. The rats were divided into three groups: Sham, MI, and SB + MI (SB216763) groups. Immunohistochemistry was used to observe the changes in cardiac morphology. A significant reduction in the sizes of fibrotic scars was observed in the SB + MI group compared to that in the MI group. SB216763 decreased the mRNA and protein expression of CD47 and NF-κB during MI. Primary rat cardiomyocytes (RCMs) and the H9c2 cell line were used to establish in vitro hypoxia models. Quantitative real-time PCR and western blotting analyses were conducted to detect mRNA and protein expression levels of CD47 and NF-κB and apoptosis-related proteins, respectively. Apoptosis of hypoxic cells was assessed using flow cytometry. SB216763 reduced the protein expression of CD47 and NF-κB in RCMs and H9c2 cells under hypoxic conditions for 12 h, and alleviated hypoxia-induced apoptosis. SN50 (an NF-κB inhibitor) also decreased CD47 protein expression in RCMs and H9c2 cells under hypoxic conditions for 12 h and protected cells from apoptosis. GSK-3ß upregulates CD47 expression in cardiac tissues after MI by activating NF-κB, which in turn leads to myocardial cell damage and apoptosis.

[Adsorption behavior of low density lipoprotein on titanium surface].

PURPOSE: The purpose of this study was to investigate the adsorption of low density lipoprotein (LDL) on titanium surface. METHODS: Pure titanium specimens were soaked with different concentrations of LDL (0, 1, 2 mg/mL). Low density lipoprotein essay was used to analyze the change of LDL adsorption on titanium surface with time going on. Scanning electron microscope(SEM) and X-ray photoelectron spectroscopy(XPS) were used to observe and analyze the adsorption of LDL on titanium surface and its effect on element composition of titanium surface. Contact angle of titanium surface was detected before and after LDL adsorption. SPSS 22.0 software package was used for statistical analysis of the data. RESULTS: The adsorption amount of LDL on titanium surface gradually increased as time went on. XPS analysis results showed that LDL was adsorbed on the titanium surface, the content of titanium and oxygen elements seemed to decrease on the titanium surface, and the hydrophilicity of the titanium surface declined. CONCLUSIONS: LDL can adsorb on titanium surface, which can change the physical and chemical properties of titanium surface to a certain extent.

Identification of Novel ARSB Genes Necessary for p-Benzoquinone Biosynthesis in the Larval Oral Secretion Participating in External Immune Defense in the Red Palm Weevil.

External secretions, composed of a variety of chemical components, are among the most important traits that endow insects with the ability to defend themselves against predators, parasites, or other adversities, especially pathogens. Thus, these exudates play a crucial role in external immunity. Red palm weevil larvae are prolific in this regard, producing large quantities of p-benzoquinone, which is present in their oral secretion. Benzoquinone with antimicrobial activity has been proven to be an active ingredient and key factor for external immunity in a previous study. To obtain a better understanding of the genetic and molecular basis of external immune secretions, we identify genes necessary for p-benzoquinone synthesis. Three novel ARSB genes, namely, RfARSB-0311, RfARSB-11581, and RfARSB-14322, are screened, isolated, and molecularly characterized on the basis of transcriptome data. To determine whether these genes are highly and specifically expressed in the secretory gland, we perform tissue/organ-specific expression profile analysis. The functions of these genes are further determined by examining the antimicrobial activity of the secretions and quantification of p-benzoquinone after RNAi. All the results reveal that the ARSB gene family can regulate the secretory volume of p-benzoquinone by participating in the biosynthesis of quinones, thus altering the host's external immune inhibitory efficiency.

Biocorrosion of pure and SLA titanium surfaces in the presence of Porphyromonas gingivalis and its effects on osteoblast behavior.

Objective: The study aims to investigate the biocorrosion behavior of Porphyromonas gingivalis on pure and SLA titanium surfaces and its effects on surface characteristics and osteoblast behavior. Methods: Pure and SLA titanium specimens were immersed in culture medium with P. gingivalis and incubated for 7 days. P. gingivalis colonization on the pure and SLA titanium surfaces was observed by scanning electron microscopy (SEM). The pure and SLA titanium surface characteristics were analyzed via X-ray photoelectron spectroscopy (XPS), surface roughness and surface wettability. The corrosion behaviors of pure and SLA titanium specimens were evaluated by electrochemical corrosion test. The osteoblast behavior of MC3T3-E1 cells on the pure and SLA titanium surfaces after P. gingivalis colonization was investigated by cell adhesion and western blot assays. Results: P. gingivalis colonized on the pure and SLA titanium surfaces was observed by SEM. The XPS analysis demonstrated reductions in the relative levels of titanium and oxygen and obvious reductions of dominant titanium dioxide (TiO2) on both titanium surfaces after immersing the metal in P. gingivalis culture. In addition, their roughness and wettability were changed. Correspondingly, the electrochemical corrosion test results revealed significant decreases in the corrosion resistance and increases in the corrosion rate of the pure and SLA titanium specimens after immersion in P. gingivalis culture. The results of the in vitro study showed that the pre-corroded pure and SLA titanium surfaces by P. gingivalis exhibited lower osteocompatibility and down-regulated the adhesion, spreading and osteogenic differentiation abilities of MC3T3-E1 cells. Conclusions: P. gingivalis was able to colonize on the pure and SLA titanium surfaces and weaken their surface properties, especially a decrease in the protective TiO2 film, which induced the biocorrosion and further negatively affected the osteoblast behavior.

Identification of lncRNAs by RNA Sequencing Analysis During in Vivo Pre-Implantation Developmental Transformation in the Goat.

Pre-implantation development is a dynamic, complex and precisely regulated process that is critical for mammalian development. There is currently no description of the role of the long noncoding RNAs (lncRNAs) during the pre-implantation stages in the goat. The in vivo transcriptomes of oocytes (n = 3) and pre-implantation stages (n=19) at seven developmental stages in the goat were analyzed by RNA sequencing (RNA-Seq). The major zygotic gene activation (ZGA) event was found to occur between the 8- and 16-cell stages in the pre-implantation stages. We identified 5,160 differentially expressed lncRNAs (DELs) in developmental stage comparisons and functional analyses of the major and minor ZGAs. Fourteen lncRNA modules were found corresponding to specific pre-implantation developmental stages by weighted gene co-expression network analysis (WGCNA). A comprehensive analysis of the lncRNAs at each developmental transition of high correlation modules was done. We also identified lncRNA-mRNA networks and hub-lncRNAs for the high correlation modules at each stage. The extensive association of lncRNA target genes with other embryonic genes suggests an important regulatory role for lncRNAs in embryonic development. These data will facilitate further exploration of the role of lncRNAs in the developmental transformation in the pre-implantation stage.

Osseointegration of titanium dental implant under fluoride exposure in rabbits: Micro-CT and histomorphometry study.

OBJECTIVE: This study aims to investigate the influence of fluoride exposure on implant osseointegration. METHODS: A total of 24 male New Zealand white rabbits were randomly divided into the control group and the fluoride exposure group. Rabbits in the control group were fed with tap water, while those in the fluoride exposure group were given 200 mg/L sodium fluoride solution. After 2-month feeding, implants were inserted into the extraction socket immediately after extraction of rabbit mandibular anterior teeth. Four rabbits in each group were sacrificed to collect the implants samples at 1, 2, and 3 months post-implantation, respectively. Radiographic and histomorphometry examinations were performed to evaluate the condition of implant osseointegration. RESULTS: Bone volume around the implants increased in a time-dependent manner in both groups. Micro-CT images illustrated that the bone mineral density (BMD) in the fluoride exposure group was significantly lower than that in the control group after implantation for 2 and 3 months. The bone-implant contact ratio (BIC) in the fluoride exposure group was much lower than that of the control group at 3 months post-implantation according to histomorphometry examination. CONCLUSIONS: In rabbit animal model, high fluoride exposure affected the quality of bone surrounding the implant and significantly reduced bone integration of the implant, especially in the late stage of osseointegration.

Prognostic Differences in Patients with Solitary and Multiple Spinal Metastases.

OBJECTIVES: To investigate the association between the number of metastases to the spine and survival in patients with metastatic spinal cord compression (MSCC), as well as the prognosis difference between patients with solitary spinal metastasis (SSM) and multiple spinal metastases (MSM). METHODS: Three institutional databases were searched to identify all patients who had undergone spinal surgery for metastatic spinal tumors between March 2002 and June 2010. As well as age and gender, preoperative medical conditions were collected from medical records, including primary tumor, preoperative Frankel score, other bone metastases, preoperative Karnofsky performance status (KPS), number of involved vertebrae, pathological fracture metastasis site, serum albumin, sphincter dysfunction and the time of developing motor deficits before surgery. Survival data were obtained from medical records or via telephone follow-ups. Univariate and multivariate predictors of overall survival for each group were assessed using the Cox proportional hazards model. RESULTS: The median postoperative survival time was 6.0 ± 0.6 months (95% confidence interval [CI] 4.8-7.2) in patients with SSM and 7.0 ± 1.0 months (95% CI 5.1-8.9) in patients with MSM (P = 0.238). The difference in survival was not significant between groups. Furthermore, univariate analysis showed that the number of spinal metastases had no significant association with survival (P = 0.075). Primary tumor (P = 0.004) and preoperative KPS (P < 0.001) were independent prognostic factors in the whole cohort; primary tumor (P = 0.020), time of developing motor deficit (P = 0.041) and preoperative KPS (P = 0.038) were independent prognostic factors in patients with SSM; while preoperative KPS (P = 0.001) and serum album level (P < 0.001) were independent prognostic factors in patients with MSM. CONCLUSION: The number of spinal metastases has not proven to be useful in predicting the prognosis for patients with MSCC. Consequently, more aggressive operations should be considered for patients with multiple spinal metastases.

Regulation of osteoblast behaviors via cross-talk between Hippo/YAP and MAPK signaling pathway under fluoride exposure.

Titanium is widely used in implant materials, while excessive fluoride may have negative effects on the osseointegration between the titanium and osteoblasts. Although the underlying mechanisms are still not clear, the mitogen-activated protein kinase (MAPK) or Yes-associated protein (YAP) signaling pathways are thought to be involved. This study evaluated the role of Hippo/YAP and MAPK signaling pathway in osteoblast behaviors under excessive fluoride exposure in vitro and in vivo. Commercially pure Ti (cp-Ti) samples were exposed to fluoride (0, 0.1, and 1.0 mM NaF) for 7 days. Cell adhesion was observed using a laser scanning confocal microscope. Cell viability and apoptosis were evaluated by CCK-8 assay and flow cytometry, respectively. The expressions of osteoblast markers and key molecules in MAPK and YAP pathway were detected by Western blot. In vivo studies were evaluated by histology methods in C57/BL6 mice model. Our results showed that 1.0 mM NaF destroyed the passivation film on cp-Ti surface, which further inhibited the osteoblast adhesion and spreading. Meanwhile, compared to other groups, 1.0 mM NaF led to a remarkable reduction in cell viability (P < 0.05), as well as increased apoptosis (P < 0.05) and downregulation of osteogenesis protein expression (P < 0.05). MAPK and YAP signaling pathways were also activated under 1.0 mM NaF exposure, and JNK seemed to regulate YAP phosphorylation in response to NaF impacts on osteoblasts. In vivo fluorosis mouse model further indicated that 100 ppm NaF group (high fluoride group) increased bone resorption and inhibited the nuclear translocation of YAP. The osteoblast behaviors were negatively altered under excessive fluoride, and MAPK/JNK axis contributed to YAP signaling activation in regulating NaF-induced osteoblast behaviors. KEY MESSAGES: • Excessive fluoride inhibited osteoblast behaviors and bone formation. • YAP and MAPK signaling pathways were activated in osteoblasts under fluoride exposure. • Fluoride regulated osteoblast behaviors via the cross-talk between YAP and MAPK.

Enhanced corrosion resistance of zinc-containing nanowires-modified titanium surface under exposure to oxidizing microenvironment.

Titanium (Ti) and its alloys as bio-implants have excellent biocompatibilities and osteogenic properties after modification of chemical composition and topography via various methods. The corrosion resistance of these modified materials is of great importance for changing oral system, while few researches have reported this point. Recently, oxidative corrosion induced by cellular metabolites has been well concerned. In this study, we explored the corrosion behaviors of four common materials (commercially pure Ti, cp-Ti; Sandblasting and acid etching-modified Ti, Ti-SLA; nanowires-modified Ti, Ti-NW; and zinc-containing nanowires-modified Ti, Ti-NW-Zn) with excellent biocompatibilities and osteogenic capacities under the macrophages induced-oxidizing microenvironment. The results showed that the materials immersed into a high oxidizing environment were more vulnerable to corrode. Meanwhile, different surfaces also showed various corrosion susceptibilities under oxidizing condition. Samples embed with zinc element exhibited more excellent corrosion resistance compared with other three surfaces exposure to excessive H2O2. Besides, we found that zinc-decorated Ti surfaces inhibited the adhesion and proliferation of macrophages on its surface and induced the M2 states of macrophages to better healing and tissue reconstruction. Most importantly, zinc-decorated Ti surfaces markedly increased the expressions of antioxidant enzyme relative genes in macrophages. It improved the oxidation microenvironment around the materials and further protected their properties. In summary, our results demonstrated that Ti-NW-Zn surfaces not only provided excellent corrosion resistance properties, but also inhibited the adhesion of macrophages. These aspects were necessary for maintaining osseointegration capacity and enhancing the corrosion resistance of Ti in numerous medical applications, particularly in dentistry.