[Advances in the Application of Hydroxyapatite Composite Materials in Bone Tissue Engineering].

Hydroxyapatite (HAp) is the main inorganic component of the bones and teeth, and it possesses bioactivity and biocompatibility. However, due to its poor mechanical performance, slow degradation speed, and lack of diversity in its function, it is difficult to apply HAp alone as a scaffold material for bone tissue engineering. By combining HAp with other types of materials, composite materials with specific properties can be prepared, and the scopes of HAp applications can be expanded. Firstly, we elaborated on the importance, and strengths and weaknesses of HAp for bone tissue engineering biomaterials and then reviewed the research status of HAp composite materials used in bone regeneration. Secondly, about hot research topics in the field of applying HAp composite materials in bone repair, we summarized the representative findings in the field, and discussions and analysis were made accordingly. Finally, we also examined the future development prospects of HAp composite bone repair materials.

Comprehensive Transcriptome Analysis of mRNA Expression Patterns Associated With Enhanced Biological Functions in Periodontal Ligament Stem Cells Subjected to Short-Term Hypoxia Pretreatment.

Short-term hypoxia pretreatment significantly enhances periodontal ligament stem cell (PDLSC)-based periodontal tissue regeneration by improving various cellular biological functions, but the underlying mechanisms remain unclear. In this study, based on RNA sequencing (RNA-seq), we comprehensively analyzed the possible regulatory mechanisms of the short-term hypoxic effects on the biological functions of healthy and inflammatory PDLSCs. A total of 134 and 164 differentially expressed genes (DEGs) were identified under healthy and inflammatory conditions, respectively. Functional enrichment analyses indicated that DEGs under both conditions share certain biological processes and pathways, including metabolic processes, developmental processes, reproductive processes, localization, immune system processes and the HIF-1 signaling pathway. The DEGs identified under inflammatory conditions were more significantly enriched in cell cycle-related processes and immune-related pathways, while DEGs identified under healthy condition were more significantly enriched in the TGF-ß signaling pathway. A protein-protein interaction network analysis of the 59 DEGs in both conditions was performed, and 15 hub genes were identified. These hub genes were mainly involved in glycolysis, the cellular response to hypoxia, cell differentiation, and immune system processes. In addition, we found that hypoxia induced significant differential expression of genes associated with proliferation, differentiation, migration, apoptosis and immunoregulation under both healthy and inflammatory conditions. This study provides comprehensive insights into the effects of short-term hypoxia on the biological functions of PDLSCs and suggests a potentially feasible strategy for improving the clinical effectiveness of cell-based periodontal tissue engineering.

Toripalimab combined with targeted therapy and chemotherapy achieves pathologic complete response in gastric carcinoma: A case report.

BACKGROUND: Neoadjuvant or perioperative chemotherapy combined with surgery can reduce postoperative recurrence and improve the long-term survival rate of patients with locally advanced resectable gastric carcinoma. Nivolumab combined with chemotherapy has been recommended by the National Comprehensive Cancer Network guidelines as a first-line therapy for advanced gastric carcinoma/ adenocarcinoma of the gastroesophageal junction and serves as the basis for immunotherapy combined with chemotherapy to become a neoadjuvant therapy. Herein, we report a case in which pathologic complete response was achieved by neoadjuvant administration of toripalimab, Herceptin, and docetaxel, oxaliplatin, calcium folinate, and fluorouracil (FLOT) chemotherapy followed by surgery for human epidermal growth factor receptor 2 (HER2)- and programmed death-ligand 1 (PD-L1)-positive locally advanced gastric carcinoma. We hope that this case will shed some light on neoadjuvant therapy for gastric carcinoma. CASE SUMMARY: The patient was diagnosed with locally advanced adenocarcinoma of the cardia. Immunohistochemistry of the baseline tissues suggested that the tissues were HER2- (fluorescent in situ hybridization) and PD-L1-positive (combined positive score = 1). The patient underwent surgery following a four-cycle neoadjuvant therapy comprising Herceptin, toripalimab, and FLOT chemotherapy. The postoperative pathological findings showed mild atypical hyperplasia of the local glands with chronic mucosal inflammation (proximal stomach), no clear residual tumor (tumor regression grade 0), no regional lymph node metastasis, and negative upper and lower cut ends. The levels of tumor markers were reduced to normal levels after re-examination. With good postoperative recovery, the four-cycle preoperative chemotherapy was continued at the same dosage as that previously administered. After the treatment, the patient was monitored every 3 mo with a follow-up of 12 mo (4 times). As of February 27, 2022, he was in a good condition without disease progression. The clinical trial registration number is E2019401. CONCLUSION: There are many ongoing studies on neoadjuvant immunotherapy combined with chemotherapy or radiotherapy; however, most of these studies are phase II studies with small cohorts. According to the results of some current studies, these combined regimens have shown promising results in terms of efficacy and safety. However, the clinical efficacy and safety of the neoadjuvant therapies used in these combined regimens need to be confirmed by additional prospective phase III clinical trials, and further exploration of molecular markers for effective populations is required.

Metformin combats high glucose-induced damage to the osteogenic differentiation of human periodontal ligament stem cells via inhibition of the NPR3-mediated MAPK pathway.

BACKGROUND: High glucose-induced damage to the osteogenic differentiation of human periodontal ligament stem cells (PDLSCs) has long been a challenge to periodontal regeneration for diabetic individuals. Metformin is an anti-hyperglycemic drug that exhibits abundant biological activities associated with cell metabolism and downstream tissue regeneration. However, how metformin combats damage to PDLSC osteogenic differentiation under high glucose and the underlying mechanisms remain unknown. METHODS: Osteogenic differentiation of PDLSCs was assessed by alkaline phosphatase (ALP) staining, ALP activity, Alizarin Red staining and quantitative assay, quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis. RNA-seq analysis was performed to screen target genes of metformin, and the effects of target genes were confirmed using lentivirus transfection. Western blot analysis was also used to detect the protein level of underlying signaling pathways. RESULTS: We found that osteogenic differentiation of PDLSCs under high glucose was decreased, and metformin addition enhanced this capacity of differentiation. Furthermore, the results of RNA-seq analysis showed that natriuretic peptide receptor 3 (NPR3) was upregulated in PDLSCs under high glucose and downregulated after metformin addition. When the underlying pathways involved were investigated, we found that upregulation of NPR3 can compromise the metformin-enhanced PDLSC osteogenic differentiation and activate the MAPK pathway (especially the p38 MAPK and Erk1/2 pathway), and that inhibition of the NPR3-mediated p38 MAPK or Erk1/2 pathway enhanced the osteogenic differentiation of PDLSCs under high glucose. CONCLUSIONS: The present study suggests that metformin may enhance the osteogenic differentiation of PDLSCs under high glucose via downregulation of NPR3 and inhibition of its downstream MAPK pathway. This is the first report identifying the involvement of NPR3-mediated MAPK pathway in the metformin-enhanced osteogenic differentiation, indicating that NPR3 antagonists, such as metformin, may be feasible therapeutics for periodontal tissue regeneration in diabetic individuals.

S100A6 overexpression is associated with poor prognosis and is epigenetically up-regulated in gastric cancer.

S100A6 has been implicated in a variety of biological functions as well as tumorigenesis. In this study, we investigated the expression status of S100A6 in relation to the clinicopathological features and prognosis of patients with gastric cancer and further explored a possible association of its expression with epigenetic regulation. S100A6 expression was remarkably increased in 67.5% of gastric cancer tissues as compared with matched noncancerous tissues. Statistical analysis demonstrated a clear correlation between high S100A6 expression and various clinicopathological features, such as depth of wall invasion, positive lymph node involvement, liver metastasis, vascular invasion, and tumor-node metastasis stage (P < 0.05 in all cases), as well as revealed that S100A6 is an independent prognostic predictor (P = 0.026) significantly related to poor prognosis (P = 0.0004). Further exploration found an inverse relationship between S100A6 expression and the methylation status of the seventh and eighth CpG sites in the promoter/first exon and the second to fifth sites in the second exon/second intron. In addition, the level of histone H3 acetylation was found to be significantly higher in S100A6-expressing cancer cells. After 5-azacytidine or trichostatin A treatment, S100A6 expression was clearly increased in S100A6 low-expressing cells. In conclusion, our results suggested that S100A6 plays an important role in the progression of gastric cancer, affecting patient prognosis, and is up-regulated by epigenetic regulation.

Over-expression of Metastasis-associated in Colon Cancer-1 (MACC1) Associates with Better Prognosis of Gastric Cancer Patients.

OBJECTIVE: The aim of this study was to detect metastasis-associated in colon cancer-1 (MACC1) expression in Chinese gastric cancer and analyze the relationship between MACC1 expression and postoperative survival. METHODS: The expression of MACC1 and c-MET protein in a sample of 128 gastric cancer tissues was detected by immunohistochemistry. A retrospective cohort study on the prognosis was carried out and data were collected from medical records. RESULTS: The positive rate of MACC1 protein expression in gastric cancer was 47.66%, higher than that in adjacent noncancerous mucosa (P<0.001). MACC1 protein expression was not related to the clinicopathological variables involved. Kaplan-Meier analysis revealed that the survival of MACC1 positive group tended to be better than that of MACC1 negative group, particularly in patients with stage III carcinoma (P=0.032). Cox regression analysis revealed that MACC1 protein over-expression in gastric cancer tended to be a protective factor with hazard ratio of 0.621 (P=0.057). Immunohistochemical analysis showed that the positive rate of c-MET protein expression was much higher in cases with positive MACC1 expression in gastric cancer (P=0.002), but P53 expression was not associated with MACC1 expression. CONCLUSION: MACC1 over-expression implies better survival and may be an independent prognostic factor for gastric cancer in Chinese patients.

[Sitagliptin inhibits lipopolysaccharide-induced inflammatory response in human gingival fibroblasts by blocking nuclear factor-κB signaling pathway].

OBJECTIVES: This study was performed to clarify the effects of sitagliptin on Porphyromonas gingivalis-lipopolysaccharide (LPS)-induced inflammatory response in human gingival fibroblasts (HGFs), explore the molecular mechanism of its roles, and provide a foundation for clinical therapeutics in periodontitis. METHODS: Healthy gingival samples were collected from the donors. HGFs were isolated with enzymic digestion method and identified. The effects of LPS and sitagliptin on cell viability were detected by cell-counting kit-8 (CCK8). The mRNA levels of inflammatory cytokines, namely, interleukin (IL)-6, IL-8, C-C motif ligand 2 (CCL2), and superoxide dismutase 2 (SOD2), were evaluated by quantity real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immune sorbent assay (ELISA) was used to measure the secretion protein levels of IL-6, IL-8, and CCL2. Western blot analysis was used to further investigate the activation of nuclear factor (NF)-κB signaling pathway. The effect of NF-κB pathway inhibitor BAY11-7082 on LPS-induced HGF inflammatory cytokines at the gene level was verified by qRT-PCR. RESULTS: Low concentrations of sitagliptin (0.1, 0.25, and 0.5 µmol·L-1) did not affect HGF growth in 24 and 48 h, whereas high concentrations of sitagliptin (5-1 000 µmol·L-1) significantly inhibited cell proliferation. Sitagliptin suppressed 5 µg·mL-1 of LPS-induced IL-6, IL-8, CCL2, and SOD2 gene expression levels in HGF in a concentration-dependent manner. Furthermore, sitagliptin significantly decreased the elevated secretion of IL-6, IL-8, and CCL2 protein induced by LPS. Western blot analysis showed that 0.5 µmol·L-1 of sitagliptin significantly inhibited LPS-induced NF-κB signaling pathway activation. Results of qRT-PCR analysis indicated that 0.5 µmol·L-1 of sitagliptin and 5 µmol·L-1 of BAY11-7082 significantly inhibited LPS-induced IL-6, IL-8, CCL2, and SOD2 gene expressions. CONCLUSIONS: Sitagliptin could significantly inhibit LPS-induced HGF inflammatory response by blocking the NF-κB signaling pathway activation.

Immunomodulatory effect of dimethyloxallyl glycine/nanosilicates-loaded fibrous structure on periodontal bone remodeling.

BACKGROUND/PURPOSE: Relieving immuno-inflammatory responses is the prerequisite step for treating periodontitis. The angiogenic small molecule, dimethyloxalylglycine (DMOG), and osteoinductive inorganic nanomaterial, nanosilicate (nSi) have a powerful effect on bone regeneration, whereas the roles in osteoimmunomodulation have not been totally uncovered. Our study aimed to explore the immunomodulatory effect of DMOG/nSi-loaded fibrous membranes on periodontal bone remodeling. MATERIALS AND METHODS: The fibrous membranes were prepared by incorporating DMOG and nSi into poly (lactic-co-glycolic acid) (PLGA) with electrospinning. The morphology features, surface chemical property and biocompatibility of DMOG/nSi-PLGA fibrous membranes were characterized. Thereafter, the fibrous membranes were implanted into rat periodontal defects, bone remodeling potential and immunomodulatory effect were evaluated by micro-computed tomography (micro-CT), histological evaluation and immunohistochemical analysis. RESULTS: DMOG/nSi-PLGA membranes possessed favorable physicochemical properties and biocompatibility. After the fibrous membranes implanted into periodontal defects, DMOG/nSi-PLGA membranes could relieve immuno-inflammatory responses of the defects (reduction of inflammatory cell infiltration, CD40L and CD11b-positive cells), increased CD206-positive M2 macrophages, and eventually facilitated periodontal bone regeneration. CONCLUSION: DMOG/nSi-PLGA fibrous membranes exert protective effects during periodontal bone defect repairing, and steer immune response towards bone regeneration. Consequently, DMOG/nSi-PLGA fibrous membranes may serve as a promising scaffold in periodontal tissue engineering.

[Effects of Exenatide-4 on proliferation, migration and osteogenic differentiation of human periodontal ligament stem cells].

PURPOSE: To investigate the effects of exendin-4(EX-4) on proliferation, migration and osteogenic differentiation of human periodontal ligament stem cells(PDLSCs). METHODS: PDLSCs were isolated and cultured using limited dilution method in vitro. Colony formation assay, osteogenic and adipogenic differentiation were applied to identify the stem cells. Immunofluorescence staining was used to detect the expression of EX-4 receptor glucagon-like peptide-1 receptor (GLP-1R) on the surface of PDLSCs. PDLSCs were stimulated with 5, 10, 20 or 50 nmol/L EX-4 in vitro. CCK-8, Transwell assay and alkaline phosphatase(ALP) activity assay were used to determine the effects of EX-4 on PDLSCs proliferation, migration and osteogenic differentiation. Quantitative real-time polymerase chain reaction was used to determine the expression of osteogenic related genes ALP, runt-related transcription factor 2(Runx2) and osteocalcin (OCN). The data were analyzed by Graphpad Prims 6.0 software package. RESULTS: PDLSCs were successfully isolated and cultivated. GLP-1R positively expressed on the surface of PDLSCs. EX-4 exerted no significant effect on PDLSCs proliferation(P>0.05). EX-4 significantly promoted migration, ALP activity and osteogenic related genes expression of PDLSCs (P<0.05). CONCLUSIONS: 10 nmol/L EX-4 could promote migration and osteogenic differentiation of PDLSCs.

Tumor microenvironment interruption: a novel anti-cancer mechanism of Proton-pump inhibitor in gastric cancer by suppressing the release of microRNA-carrying exosomes.

Poor prognosis of gastric cancer is related to not only malignancy of gastric cancer cells, but also the tumor microenvironment. Thus drugs, which can inhibit both of them, are urgently needed to be explored. Studies on effect of Proton-pump inhibitors (PPIs) in anti-neoplasms are increasing, but is rare in gastric in gastric cancer. Here we investigated how the gastric cancer microenvironment is regulated by PPIs. The objective response rate of gastric cancer patients in our hospital treated by PPIs is investigated. PPIs' effects were further explored by observing the change of microRNAs, cytokines, cellular apoptosis. Bioinformatic pathway analysis of microarray was used to discover the pathway involved in PPIs' regulation of gastric cancer microenvironments. Immunoblotting assays and qRT-PCR were used to define molecular events with PPIs treatment. We report here that PPIs can improve the prognosis of advanced gastric cancer patients; and inhibit the progress of gastric cancer both in vivo and in vitro. Moreover, high dose of PPIs can regulate the pathway associated with tumor malignancy and microenvironment via inhibiting the release of exosomes, which packed microRNAs. PPIs can inhibit the transformation of CAFs (cancer associated fibroblasts) and cytokines released from CAFs. In addition, PPIs inhibit the malignancy of gastric cancer through regulating HIF-1α-FOXO1 axis. High dose of PPIs can inhibit malignancy of gastric cancer and regulate its surrounding tumor microenvironment. This finding suggests that PPIs maybe of potential value as a therapeutic tool for treatment of gastric cancer.

Systemic BMSC homing in the regeneration of pulp-like tissue and the enhancing effect of stromal cell-derived factor-1 on BMSC homing.

Pulp regeneration caused by endogenous cells homing has become the new research spot in endodontics. However, the source of functional cells that are involved in and contributed to the reconstituting process has not been identified. In this study, the possible role of systemical BMSC in pulp regeneration and the effect of stromal cell-derived factor-1 (SDF-1) on stem cell recruitment and angiogenesis were evaluated. 54 mice were divided into three groups: SDF-1 group (subcutaneous pockets containing roots with SDF-1 absorbed neutralized collagen gel and the green fluorescent protein (GFP) positive BMSCs transplantation via the tail vein), SDF-1-free group (pockets containing roots with gel alone and GFP + BMSCs transplantation) and Control group (pockets containing roots with gel alone). The animals were sacrificed after the roots were implanted into subcutaneous pockets for 3 weeks. Histomorphometric analysis was performed to evaluate the regenerated tissue in the canal by hematoxylin and eosin (HE) staining. The homing of the transplanted BMSCs was monitored with a fluorescence microscope and immunohistochemical analysis. The expression of ALP in new formed tissue was detected immunohistochemically. Dental-pulp-like tissue and new vessels were regenerated and GFP-positive BMSCs and expression of ALP could be observed in both SDF-1 group and SDF-1-free group. Furthermore, more GFP+ cells, stronger expression of ALP and stronger angiogenesis were found in the SDF-1 group than in the SDF-1-free group. To conclude, systemic BMSC can home to the root canal and participate in dental-pulp-like tissue regeneration. Intracanal application of SDF-1 may enhance BMSC homing efficiency and angiogenesis.

Change of SPARC expression after chemotherapy in gastric cancer.

OBJECTIVE: The expression of tumor biomarkers may change after chemotherapy. However, whether secreted protein acidic and rich in cysteine (SPARC) expression changes after chemotherapy in gastric cancer (GC) is unclear. This study investigated the influence of chemotherapy on SPARC expression in GC. METHODS: Immunohistochemistry was used to analyze SPARC expression in 132 GC cases (including 54 cases with preoperative chemotherapy and 78 cases without preoperative chemotherapy). SPARC expression of postoperative specimens with and without preoperative chemotherapy was assessed to analyze the influence of chemotherapy on SPARC expression. RESULTS: SPARC was highly expressed in GC compared with the desmoplastic stroma surrounding tumor cells and noncancerous tissues. High SPARC expression was correlated with invasion depth, lymph node, and TNM stage. After chemotherapy, a lower proportion of high SPARC expression was observed in patients with preoperative chemotherapy than in the controls. For 54 patients with preoperative chemotherapy, gross type, histology, depth of invasion, lymph node, TNM stage, and SPARC expression were related to overall survival. Further multivariate analysis showed that lymph node, histology, and SPARC expression after chemotherapy were independent prognostic factors. CONCLUSION: SPARC expression may change after chemotherapy in GC. SPARC expression should be reassessed for patients with GC after chemotherapy.

[Construction and identification of a recombinant lentiviral expression plasmid pLentiTrident1-hBMP2-Neo-hNGF].

PURPOSE: To construct and confirm a recombinant lentiviral vector containing human bone morphogenetic protein 2 (hBMP2) and human nerve growth factor (hNGF). METHODS: The Neomycin gene was digested from pLentiTrident1-EGFP-Neo and then was subcloned into lentiviral vector. The hBMP2 and hNGF genes were amplified by polymerase chain reaction (PCR), and then the PCR product was inserted to proper sites of the vector. Finally, the recombinant vector pLentiTrident1-hBMP2-Neo-hNGF was confirmed by agarose gel electrophoresis and DNA sequence analysis. RESULTS: The construction of recombinant lentiviral vector pLentiTrident-hBMP2 -Neo-hNGF was confirmed through restriction enzyme maping analysis and DNA sequencing. CONCLUSIONS: The recombinant lentiviral vector which can coexpress hBMP2 and hNGF is successfully constructed,which lays a solid foundation of studying the effect of neuro factors on bone regeneration.

Osteopromotive activity of a novel pyrazole carboxamide derivative.

AIMS: To investigate the effect of 1-(4-(tert-butyl)benzyl)-N-(4-methoxyphenyl)-3-phenyl-1H-pyrazole-5-carboxamide (Pyr-C) on the proliferation and osteogenic differentiation of MC3T3-E1 cells. MATERIALS & METHODS: MTT and BrdU incorporation assay were used to determine cell survival and proliferation. The gene expression levels of osteogenic markers were determined using real-time PCR and ALP activity was detected. Western-blot analysis was used to determine the protein expression of BSP and OPN. The long-term effect of Pyr-C on mineralization deposition was measured by Alizarin Red Staining. RESULTS: Pyr-C inhibited cell proliferation and increased ALP activity. Gene expression of ALP, BSP, OCN, Runx2, and Osterix was up-regulated in Pyr-C-induced group. Pyr-C increased the protein expression of BSP at day 7, 14 and 21, and OPN at day 14, 21 and 28. Meanwhile, Pyr-C enhanced the mineral deposition. CONCLUSION: Pyr-C inhibits proliferation and stimulates osteogenic differentiation of MC3T3-E1 cells.

[Clinical value of serum CEA, CA19-9, CA72-4 and CA242 in the diagnosis and prognosis of gastric cancer].

OBJECTIVE: To investigate the clinical value of tumor markers CEA, CA19-9, CA72-4 and CA242 in the diagnosis and prognosis of patients with gastric cancer. METHODS: One hundred and sixty gastric cancer patients who had received treatment from 2002 to 2007 at the Beijing Cancer Hospital were retrospectively analyzed. Blood samples were taken from patients upon admission to the hospital, and CEA, CA19-9, CA72-4, CA242 levels were detected. Statistical analysis was performed to identify the clinical value of these tumor markers in diagnosis and prognosis. RESULTS: On initial diagnosis, the positive rates of CEA, CA19-9, CA72-4 and CA242 were 37.7%, 26.7%, 37.6% and 21.3%, respectively, and the positive rate of combined detection was 62.9%. CEA was more frequently positive in patients with lymph node metastasis (P=0.029); CA72-4 was more frequently positive in patients with vascular involvement and advanced stage (P=0.039, P=0.011). Multivaraite analysis showed that CA72-4 was an independent prognostic factor (P=0.012). Patients with positive CA72-4 carried a 2.147-fold increased risk of death than those with negative CA72-4. Kaplan-Meier analysis showed that patients with positive CA19-9 or positive CA72-4 had worse survival than those with negative CA19-9 or CA72-4 (P=0.006, P=0.002). CONCLUSIONS: Tumor markers including CEA, CA19-9, CA72-4 and CA242 have clinical significance and prognostic value in patients with gastric cancer. Combined detection of four tumor markers can increase the positive rate. CA72-4 is an independent prognostic factor. CA19-9 and CA72-4 are associated with the prognosis of patients with gastric cancer.

[Quantitative detection of human cytomegalovirus in aggressive and chronic periodontitis lesions].

OBJECTIVE: To establish a quantitative real-time PCR assay for the detection of human cytomegalovirus (HCMV) DNA load in subgingival specimens from the patients with aggressive and chronic periodontitis, and to investigate the relationship between HCMV infection and the periodontal status. METHODS: A total of 114 subgingival plaque specimens were taken from 18 subjects with aggressive priodontiti (AgP), 24 subjects with chronic periodontitis (CP) and 15 healthy control subjects. Standard quantification was performed with recombinant plasmid containing a conserved fragment of HCMV. The SYBR Green I fluorescent quantitative real-time PCR assay was established based on positive plasmid. HCMV DNA load in the specimens were detected with quantitative real-time PCR based on SYBR Green I fluorescence. RESULTS: HCMV were detected in 58.3% of AgP sites and 41.7% of CP sites, however, only 6.7% of periodontally-healthy sites were HCMV positive. The detection rate of HCMV in periodontitis lesions was significantly higher than in periodontal health (P < 0.01). High copy-counts more than 10(4) of HCMV were detected in 33.3% of AgP sites, which were significantly higher than in CP sites (10.4%) (P < 0.05). CONCLUSION: Subgingival infection with HCMV is closely associated with periodontitis. Active HCMV infection may be related to the rapid tissue destruction of AgP.

A pilot study evaluating the effect of recombinant human bone morphogenetic protein-2 and recombinant human beta-nerve growth factor on the healing of Class III furcation defects in dogs.

BACKGROUND: The quantity of regenerated bone induced by recombinant human bone morphogenetic protein-2 (rhBMP2) is encouraging, but sometimes the quality is inferior. Recombinant human beta-nerve growth factor (rh beta-NGF) plays a major role in bone remodeling. This study evaluates the quality and quantity of regenerated bone in periodontal regeneration following topical application of the two growth factors to Class III furcation defects. METHODS: Thirty-six inflamed Class III furcation defects were created in six beagle dogs at sites of mandibular premolars 2, 3, and 4, and then biodegradable hydrogel incorporating rhBMP2 and rh beta-NGF was topically applied to the defects. The groupings were as follows: G1, untreated (control group A); G2, carrier alone (control group B); G3, 0.4% rhBMP2 + carrier; G4, 2% rh beta-NGF + carrier; G5, 0.4% rhBMP2 + 2% rh beta-NGF + carrier; and G6, 0.2% rhBMP2 + 1% rh beta-NGF + carrier. Eight weeks after application, the quality and quantity of regenerated tissue were evaluated by scanning electron microscopy observation, calcium/phosphorus ratio analysis, and histologic evaluation. RESULTS: The regenerated bone in G5 exhibited the highest calcium/phosphorus ratio among all groups and showed a denser structure with more calcified substances on the collagen fiber surface than that in the other groups. Histomorphometric analysis revealed that 0.4% rhBMP2 + 2% rh beta-NGF promoted the highest percentage of periodontal regeneration among all groups. CONCLUSION: The results of this pilot study suggest that a topical application of rhBMP2 and rh beta-NGF may improve the quality and quantity of regenerated bone in artificially created Class III furcation defects of beagle dogs.

[Biological effects of phenytoin on cultured human periodontal ligament fibroblasts in vitro].

OBJECTIVE: To study the biological effects of phenytoin (PHT) on cultured human periodontal ligament fibroblasts (hPDLF), and explore the possibility of its accelerating periodontal regeneration. METHODS: Increasing concentrations of PHT (1, 5, 20, 100, 500, 2 500 mg/L) were added into the medium of the fourth passage of cultured hPDLF, respectively. After co-incubated for 3 days, cell proliferation activity, the total amount of protein and alkaline phosphatase (ALP) activity were detected. Mineralized sodium and PHT (20, 100, 500 mg/L) were added into the medium of the fourth passage hPDLF. After co-incubated, the mineralized nodules formation were detected by Von Kossa staining. The third passage hPDLF were stimulated by PHT (20, 100 mg/L), bone morphogenetic protein-2 (BMP-2) concentration was analyzed by enzyme linked immunosorbent sandwich assay (ELISA). RESULTS: At the concentration of 20 or 100 mg/L, PHT significantly enhanced the proliferating activity and ALP activity of hPDLF (P<0.01). PHT at 100 mg/L could increase protein synthesis of hPDLF (P<0.05). The capability of mineralization and BMP-2 expression of hPDLF were increased significantly (P<0.01) in 100 mg/L group when compared with that in the control group. However, higher concentration (2 500 mg/L) not only changed cell morphology, but also significantly inhibited cell activity. CONCLUSION: The results suggested that proper doses of PHT could promote proliferation and biosynthesis and also enhance osteogenesis by increasing the differentiation, mineralization and BMP-2 expression of hPDLF while higher concentrations of PHT had cytotoxic effect.

[Clinical effect of minocycline as adjunctive therapy to scaling and root planning on treatment of chronic periodontitis].

OBJECTIVE: To evaluate the efficacy of minocycline as an adjunct to scaling and root planning (SRP) in treating chronic periodontitis. METHODS: 64 male smokers with moderate to advanced periodontitis were randomly divided into two groups: SRP alone (SRP) and SRP plus minocycline (SRP+M). All clinical parameters including plaque index (Pll), gingival index (GI), bleeding on probing (BOP), probing depth (PD) and attachment gain were recorded at baseline, 3 and 6 months after treatment. RESULTS: According to PlI, GI and BOP, there was no significant difference between the two groups at 3 and 6 months after periodontal therapy (1 > 0.05). However, PD reduction and attachment gain were significantly greater for SRP+M than that for SRP (P < 0.05). For SRP+M and SRP groups, PD reduction were 1.98 mm and 1.32 mm, and attachment gain were 1.87 mm and 1.14 mm respectively. Deep pockets in SRP+M group showed more obvious PD reduction (3.48 mm versus 2.21 mm, P < 0.01) and attachment gain (2.62 mm versus 1.23 zmm, P < 0.01) than that in SRP group. CONCLUSION: Treatment with SRP plus locally delivered minocycline is more effective than SRP alone in male smokers with chronic periodontitis. Mechanical debridement plus locally delivered antibiotics are recommended especially for smokers with deep pocket periodontitis.

[Expression of epidermal growth factor receptor in human periodontal ligament cells during their mineralization in vitro].

OBJECTIVE: To investigate the expression of epidermal growth factor receptor (EGFR) during the mineralization of human periodontal ligament cells (hPDLC) in vitro. METHODS: Studies using specific antibodies to immunolocalize EGFR in the mineral differentiating hPDLC were undertaken to investigate the different expression during the inducing process. In situ hybridization and RT-PCR technique were used to investigate the transcripts encoding the protein of EGFR. RESULTS: The results showed that immunocytochemical labeling gradually decreased following the elong of the induce time, downing to nearly negative at the 4th week and the signal of EGFR transcripts was weaker in the induced hPDLC than that in uninduced. CONCLUSION: EGFR has a negative regulation function during the mineralization of hPDLC.