A comparative study of the effects of platelet-rich fibrin, concentrated growth factor and platelet-poor plasma on the healing of tooth extraction sockets in rabbits.

BACKGROUND: Autologous platelet concentrate has been widely used to encourage the regeneration of hard and soft tissues. Up to now, there are three generations of autologous platelet concentrates. Many studies have shown that the three autologous concentrates have different effects, but the specific diversities have not been studied. The purpose of this study was to explore and compare the effects of platelet-rich fibrin, concentrated growth factor and platelet-poor plasma on the healing of tooth extraction sockets in New Zealand rabbits. METHODS: A total of 24 healthy male New Zealand white rabbits aged 8-12 weeks were selected. The experimental animals were randomly divided into four groups: three experimental groups were respectively implanted with PPP, CGF and PRF gel after bilateral mandibular anterior teeth were extracted, and the control group did not implant any material. The alveolar bone of the mandibular anterior region was taken at 2, 4 and 8 weeks after operation. The height and width of the extraction wound were detected by CBCT, the growth of the new bone was observed by HE and Masson staining, and the expression of osteogenic genes was detected by real-time PCR. Data were analyzed using IBM SPSS statistical package 22.0. RESULTS: The radiological results showed that alveolar bone resorption in all groups gradually increased over time. However, the experimental groups showed lower amounts of bone resorption. The histological results showed that new bone formation was observed in all groups. Over time, the new bone trabeculae of the CGF group became closely aligned while those in the PPP and PRF groups remained scattered. PCR results showed that the expression of BMP-2 and ALP was higher in the experimental groups than the control group. CONCLUSION: In conclusion, the application of PRF, CGF and PPP in tooth extraction sockets effectively promoted bone regeneration. CGF showed more effective bone induction and tissue regeneration ability in the long term.

Src promotes EGF-induced epithelial-to-mesenchymal transition and migration in gastric cancer cells by upregulating ZEB1 and ZEB2 through AKT.

Epithelial-to-mesenchymal transition (EMT) plays important roles in the migration, invasion, and metastasis of cancer cells. However, the role of Src in epidermal growth factor (EGF)-induced EMT and migration in gastric cancer cells remains to be clarified. In the current study, the effect of Src on EGF-stimulated EMT and migration was explored in gastric cancer cells. EGF induced EMT in gastric cancer cells and increased their migratory ability, which was accompanied by the phosphorylation of Src. PP2, the Src inhibitor, markedly suppressed EGF-mediated EMT and migration in gastric cancer cells. Additionally, EGF-stimulated upregulation of zinc finger E-box binding homeobox 1 (ZEB1) and zinc finger E-box binding homeobox 2 (ZEB2) was significantly repressed by PP2. Further analysis showed that EGF-stimulated phosphorylation of protein kinase B (AKT) was almost completely abolished by PP2, whereas that of extracellular signal-regulated kinase (ERK), signal transducer and activator of transcription 3 (STAT3) was only mildly suppressed. Moreover, LY294002, the AKT inhibitor, significantly inhibited EGF-induced upregulation of ZEB1 and ZEB2 as well as EMT and migration stimulated by EGF in gastric cancer cells. However, neither ERK inhibitor nor STAT3 inhibitor repressed EGF-induced EMT-related changes. Taken together, these results suggest that Src promotes EGF-stimulated EMT and migration by upregulation of ZEB1 and ZEB2 through AKT signaling pathway in gastric cancer cells.

Continuous and low-carbon production of biomass flash graphene.

Flash Joule heating (FJH) is an emerging and profitable technology for converting inexhaustible biomass into flash graphene (FG). However, it is challenging to produce biomass FG continuously due to the lack of an integrated device. Furthermore, the high-carbon footprint induced by both excessive energy allocation for massive pyrolytic volatiles release and carbon black utilization in alternating current-FJH (AC-FJH) reaction exacerbates this challenge. Here, we create an integrated automatic system with energy requirement-oriented allocation to achieve continuous biomass FG production with a much lower carbon footprint. The programmable logic controller flexibly coordinated the FJH modular components to realize the turnover of biomass FG production. Furthermore, we propose pyrolysis-FJH nexus to achieve biomass FG production. Initially, we utilize pyrolysis to release biomass pyrolytic volatiles, and subsequently carry out the FJH reaction to focus on optimizing the FG structure. Importantly, biochar with appropriate resistance is self-sufficient to initiate the FJH reaction. Accordingly, the medium-temperature biochar-based FG production without carbon black utilization exhibited low carbon emission (1.9 g CO2-eq g-1 graphene), equivalent to a reduction of up to ~86.1% compared to biomass-based FG production. Undoubtedly, this integrated automatic system assisted by pyrolysis-FJH nexus can facilitate biomass FG into a broad spectrum of applications.

The biological activity of H. pylori SlyD in vitro.

AIM: To investigate the biological activity of the H. pylori SlyD in vitro. METHODS: Helicobacter pylori (H.pylori) slyD prokaryotic expression vector was carried out in Escherichia coli (E.coli), and recombination SlyD (rSlyD) was purified by immobilized metal affinity chromatography. The proliferation, apoptosis, invasion, transformation effects of rSlyD on AGS cells was detected by CCK-8, cell cycle, caspase-3 activity, matrigel invasion assay, and double-deck soft agar colony forming efficiency. In addition, the expressions of PCNA, KI-67, caspase-3, and MMP-9 were detected by western blot and immunofluorescence assay, respectively. RESULTS: The CCK-8 assay revealed that cell proliferation was increased in a time and dose-dependent manner in AGS + rSlyD group compared with that of AGS or AGS + PBS group (p < .05). There are significant difference of PCNA and KI67 expressions among AGS, AGS + PBS, AGS + rSlyD groups (p < .05). Soft agar colony formation assay revealed the colony number (foci>100 µm) in AGS + rSlyD group was 26.3 ± 7.09, whereas 5.6 ± 1.15 in AGS and 5.0 ± 1.0 in AGS + PBS groups, respectively (p < .01). Colorimetric enzyme assay revealed the activity of caspase-3 was decreased to 31.45 ± 0.49 after treatment with rSlyD, whereas 55.5 ± 0.43 in AGS and 55.1 ± 0.25 in AGS + PBS group, respectively (p < .001). Similar caspase-3 expression also was confirmed by Western blot. The number of invasive cells in transwell chambers assay is 196.66 ± 40.41 in AGS + rSlyD group higher than 85 ± 22.9 in AGS or 81.66 ± 15.27 in AGS + PBS group, respectively (p < .001). The MMP-9 expression in AGS + rSlyD group was also higher than that of AGS or AGS + PBS group. CONCLUSION: These results suggest that the HpSlyD may play an important role in disturbing cell proliferation, apoptosis, and enhancing cell transformation and invasion in the AGS cell line. HpSlyD might contribute to gastric pathogenicity in H.pylori-associated diseases.

Differential Proteomic Analysis Reveals Protein Networks and Pathways that May Contribute to Helicobacter pylori FKBP-Type PPIase-Associated Gastric Diseases.

PURPOSE: Though Helicobacter pylori (H. pylori) has been classified as class I carcinogen, key virulence factor generated by H. pylori that causes gastric cancer remains to be fully determined. Recently, we identified a gastric cancer-associated H. pylori gene, peptidylprolyl isomerase-FK506 binding protein (PPIase-FKBP), and showed that PPIase-FKBP was capable of inducing oncogenic transformation of gastric epithelial cells. But its mechanism was unclear. EXPERIMENTAL DESIGN: We carried out a comparative proteomic analysis of human gastric epithelial cells that either express PPIase-FKBP or green fluorescent protein using 2-DE and then MALDI-TOF-MS/MS. RESULTS: Our results identified 28 differentially expressed proteins induced by PPIase-FKBP. These proteins participate in some cellular biological processes, such as cell proliferation, cell apoptosis and DNA replication, mRNA splicing, and protein biosynthesis. Ingenuity Pathway Analysis categorized the 28 proteins into two molecular interaction networks, involved primarily in cancer and gastrointestinal diseases. CONCLUSIONS AND CLINICAL RELEVANCE: Our results provided insight on the protein interaction networks and signaling pathways that may contribute to PPIase-FKBP-associated gastric diseases and may lead to a better understanding of the mechanisms indicating the oncogenic effects of H. pylori PPIase-FKBP.

E3 Ubiquitin Ligase Cbl-b Prevents Tumor Metastasis by Maintaining the Epithelial Phenotype in Multiple Drug-Resistant Gastric and Breast Cancer Cells.

Multiple drug resistance (MDR) and metastasis are two major factors that contribute to the failure of cancer treatment. However, the relationship between MDR and metastasis has not been characterized. Additionally, the role of the E3 ubiquitin ligase Cbl-b in metastasis of MDR gastric and breast cancer is not well known. In the present study, we found that MDR gastric and breast cancer cells possess a typical mesenchymal phenotype and enhanced cell migration capacity. Additionally, Cbl-b is poorly expressed in MDR gastric and breast cancer cells. In MDR gastric adenocarcinoma tissues, gastric cancer patients with low Cbl-b expression were more likely to have tumor invasion (P=.016) and lymph node metastasis (P=.007). Moreover, overexpression of Cbl-b reduced cell migration in MDR cell cultures both in vitro and in vivo. Cbl-b overexpression also prevented EMT by inducing ubiquitination and degradation of EGFR, leading to inhibition of the EGFR-ERK/Akt-miR-200c-ZEB1 axis. However, further overexpression of EGFR on a background of Cbl-b overexpression restored both the mesenchymal phenotype and cell migration capacity of MDR gastric and breast cancer cells. These results suggest that Cbl-b is an important factor for maintenance of the epithelial phenotype and inhibition of cell migration in MDR gastric and breast cancer cells.

SPARC expression in gastric cancer predicts poor prognosis: Results from a clinical cohort, pooled analysis and GSEA assay.

BACKGROUND: The prognostic role of Secreted Protein Acidic and Rich in Cysteine (SPARC) in gastric cancer (GC) remains controversial. We investigated the clinical significance, the survival relevance, and potential function of SPARC in GC with resected samples, online gene set GSE62254, and cell line SGC7901. RESULTS: High immunostaining of SPARC significantly correlated with tumor differentiation (P = 0.004), and independently predicted shorter overall survival (OS) (HR = 1.446, P = 0.022), based on the current IHC evaluation. The accuracy of the results was further validated with 1000 times bootstrapping and the time-dependent receiver-operating characteristics (ROC) curves. The meta-analysis (pooled HR = 1.60, 95% CI: 1.01-2.53) confirmed SPARC as the predictor for reduced OS in GC. Moreover, the association between enhanced SPARC expression and Adriamycin (Adr) sensitivity was revealed by GSEA, and then confirmed by comparative cellular experiments, such as the protein level analysis of SGC7901and SGC7901/Adr cell line. MATERIALS AND METHODS: Immunohistochemistry (IHC) method was used to detect SPARC expression in 137 GC cases. Meta-analysis was performed based on 5 studies published in English on PubMed up to March 2016. GSEA was performed using online data set GSE62254 and GC-related functional gene sets derived from molecular signatures database (MSigDB). Western Blot was carried out to compare protein-level differences between gastric carcinoma SGC7901 cell line and Adr resistant SGC7901/Adr cell line. MTT assay was done to confirm the induction of SPARC on Adr sensitivity. CONCLUSIONS: Increased SPARC expression in GC led to a worse clinical outcome of patients and might induce Adr sensitivity of GC cells.

Secreted protein acidic and rich in cysteine antagonizes bufalin-induced apoptosis in gastric cancer cells.

Bufalin is an active compound in the traditional Chinese medicine Chan Su, which has been shown to induce apoptosis in a range of cancer cell types. However, certain gastric cancer cells are known to be resistant to bufalin. Intracellular secreted protein acidic and rich in cysteine (SPARC) regulates proliferation and apoptosis. This study aimed to evaluate the role of SPARC in bufalin-induced apoptosis in SGC7901 and MGC803 gastric cancer cells. SGC7901 cells with high SPARC expression were more resistant to bufalin than MGC803 cells with low SPARC expression. This resistance was significantly reversed by small interfering (si)RNA-mediated knockdown of SPARC. Furthermore, it was shown that SPARC negatively regulated bufalin-induced intrinsic apoptosis by protecting mitochondrial integrity, decreasing the release of cytoplasmic cytochrome c and increasing the ratio of Bcl-2/Bax. In addition, SPARC overcame bufalin-induced G2/M phase arrest by increasing levels of Cyclin B1 and Cyclin A protein expression. SPARC also activated cellular survival signals, including Src and Akt, but not extracellular signal-regulated kinase. This study demonstrated that SPARC antagonizes bufalin-induced apoptosis via inhibition of the intrinsic apoptosis pathway, inhibition of cell cycle arrest and activation of certain pathways involved in proliferation. This provides novel evidence for SPARC as a potential target by which to sensitize gastric cancer cells to bufalin.

Helicobacter pylori FKBP-type PPIase promotes gastric epithelial cell proliferation and anchorage-independent growth through activation of ERK-mediated mitogenic signaling pathway.

Though Helicobacter pylori (H. pylori) has been classified as class I carcinogen, key virulence factor(s) generated by H. pylori that causes gastric cancer remains to be fully determined. Here, we show that deletion of peptidyl-prolyl cis-trans isomerase (PPIase) prevented H. pylori from stimulating human gastric epithelial cell (AGS) proliferation. Consistent with this observation, ectopic expression of H. pylori PPIase promoted AGS cell proliferation and anchorage-independent growth. To gain insight into the biochemical mechanism of PPIase-induced effect, early signal events involved in mitogenic signaling pathways were evaluated. Expression of H. pylori PPIase caused an increase in basal as well as EGF-stimulated phosphorylation of ERK and EGF receptor at Tyr1086. Treatment with MEK inhibitor completely blocked PPIase-induced cell proliferation. Our results suggest that H. pylori PPIase has the potential to activate mitogenic signaling pathway and to promote transformation of gastric epithelial cells. H. pylori PPIase may represent a novel target for therapeutic management of gastric cancer patients.