COX-2/PGE2/VEGF signaling promotes ERK-mediated BMSCs osteogenic differentiation under hypoxia by the paracrine action of ECs.

Understanding the crosstalk between endothelial cells (ECs) and bone-marrow mesenchymal stem cells (BMSCs) in response to hypoxic environments and deciphering of the underlying mechanisms are of great relevance for better application of BMSCs in tissue engineering. Here, we demonstrated that hypoxia promoted BMSCs proliferation, colony formation, osteogenic markers expression, mineralization, and extracellular signal-regulated protein kinase (ERK) phosphorylation, and that PD98059 (ERK inhibitor) blocked hypoxia-induced osteogenic differentiation. Hypoxia enhanced ECs migration, cyclooxygenase 2 (COX-2) and integrin αvß3 expression, and prostaglandin E2 (PGE2), vascular endothelial growth factor (VEGF) secretion. NS398 (selective COX-2 inhibitor) and LM609 (integrin αvß3 specific inhibitor) impaired the ECs response to hypoxia, and exogenous PGE2 partially reversed the effects of NS398. BMSCs: ECs co-culture under hypoxia upregulated BMSCs osteogenesis and ERK phosphorylation, as well as ECs migration, integrin αvß3 expression, and PGE2 and VEGF secretion. NS398 (pretreated ECs) lessened PGE2, VEGF concentrations of the co-culture system. NS398-treated ECs and AH6809 (combined EP1/2 antagonist)/L-798106 (selective EP3 antagonist)/L-161982 (selective EP4 antagonist)/SU5416 [VEGF receptor (VEGFR) inhibitor]-treated BMSCs impaired the co-cultured ECs-induced enhancement of BMSCs osteogenic differentiation. In conclusion, hypoxia enhances BMSCs proliferation and ERK-mediated osteogenic differentiation, and augments the COX-2-dependent PGE2 and VEGF release, integrin αvß3 expression, and migration of ECs. COX-2/PGE2/VEGF signaling is involved in intercellular BMSCs: ECs communication under hypoxia.

Dkk-1-TNF-α crosstalk regulates MC3T3E1 pre-osteoblast proliferation and differentiation under mechanical stress through the ERK signaling pathway.

The study aims to explore the role of the ERK signaling pathway in the crosstalk between Dkk-1 and TNF-α in MC3T3E1 pre-osteoblasts under cyclic tensile/compressive stress. A forced four-point bending system was used to apply cyclic uniaxial tensile/compressive strain (2000 µ, 0.5 Hz) to MC3T3E1 cells. Dkk-1 and TNF-α expression were upregulated in MC3T3E1 cells under compressive strain. Cell proliferation, the cell cycle, osteogenesis-related gene (Wnt5a, Runx2, Osterix) expression, ß-catenin expression, and the p-ERK/ERK ratio were significantly enhanced, whereas apoptosis, the RANKL/OPG ratio, and TNF-α expression were significantly attenuated, by Dkk-1 silencing. Dkk-1 expression increased and the effects of Dkk-1 silencing were reversed when exogenous TNF-α was added. Mechanically, TNF-α crosstalked with Dkk-1 through ERK signaling in MC3T3E1 cells. ERK signaling blockade impaired Dkk-1-induced TNF-α expression and TNF-α-mediated Dkk-1 expression. Dkk-1 and TNF-α crosstalked, partially through ERK signaling, in MC3T3E1 cells under compressive/tensile strain, synergistically modulating various biological behaviors of the cells. These findings not only provide mechanical insight into the cellular events and molecular regulation of orthodontic tooth movement (OTM), but also aid the development of novel strategies to accelerate OTM.

Comparison of the therapeutic effects of mesenchymal stem cells derived from human dental pulp (DP), adipose tissue (AD), placental amniotic membrane (PM), and umbilical cord (UC) on postmenopausal osteoporosis.

Background: Osteoporosis is a systemic bone disease characterized by bone loss and microstructural degeneration. Recent preclinical and clinical trials have further demonstrated that the transplantation of mesenchymal stem cells (MSCs) derived from human adipose tissue (AD), dental pulp (DP), placental amniotic membrane (AM), and umbilical cord (UC) tissues can serve as an effective form of cell therapy for osteoporosis. However, MSC-mediated osteoimmunology and the ability of these cells to regulate osteoclast-osteoblast differentiation varies markedly among different types of MSCs. Methods: In this study, we investigated whether transplanted allogeneic MSCs derived from AD, DP, AM, and UC tissues were able to prevent osteoporosis in an ovariectomy (OVX)-induced mouse model of osteoporosis. The homing and immunomodulatory ability of these cells as well as their effects on osteoblastogenesis and the maintenance of bone formation were compared for four types of MSCs to determine the ideal source of MSCs for the cell therapy-based treatment of OVX-induced osteoporosis. The bone formation and bone resorption ability of these four types of MSCs were analyzed using micro-computed tomography analyses and histological staining. In addition, cytokine array-based analyses of serological markers and bioluminescence imaging assays were employed to evaluate cell survival and homing efficiency. Immune regulation was determined by flow cytometer assay to reflect the mechanisms of osteoporosis treatment. Conclusion: These analyses demonstrated that MSCs isolated from different tissues have the capacity to treat osteoporosis when transplanted in vivo. Importantly, DP-MSCs infusion was able to maintain trabecular bone mass more efficiently with corresponding improvements in trabecular bone volume, mineral density, number, and separation. Among the tested MSC types, DP-MSCs were also found to exhibit greater immunoregulatory capabilities, regulating the Th17/Treg and M1/M2 ratios. These data thus suggest that DP-MSCs may represent an effective tool for the treatment of osteoporosis.

A breakthrough in periodontitis treatment: Revealing the pharmacodynamic substances and mechanisms of Kouqiangjie formula.

ETHNOPHARMACOLOGY RELEVANCE: Periodontitis, a complex inflammatory disease, significantly affects people's lives. Traditional Chinese multi-herbal formulas, composed of various herbs, exhibit their therapeutic efficacy holistically. Kouqiangjie Formula (KQJF), comprising 12 herbs including Rhizoma smilacis glabrae, Polygonatum sibiricum Delar. ex Redoute, Taraxacum mongolicum Hand.-Mazz, etc., has been clinically proven to effectively treat periodontitis. However, the potential active substances conferring these effects and their mechanisms of action remain unclear. AIM OF THE STUDY: The current investigation endeavours to utilize Ultra Performance Liquid Chromatography Quadrupole Time of Flight Mass Spectrometry (UPLC-Q-TOF-MS), network pharmacology, and in vivo animal experiment confirmation to explore the plausible bioactive compounds and operational mechanisms underpinning KQJF's therapeutic impact on periodontitis. MATERIALS AND METHODS: Using the UPLC-Q-TOF-MS technique, we deciphered the chemical constituents of KQJF. Network pharmacology was employed to earmark key bioactive elements, forecast principal targets, and operational pathways which were later substantiated through molecular docking. Experimental validations were carried out in a periodontitis animal model using a range of techniques, including micro-CT, H&E staining, qRT-PCR, and protein blotting procedures, providing comprehensive verification of our initial assumptions. RESULTS: Utilizing UPLC-Q-TOF-MS, we characterized 87 individual chemical constituents in KQJF. Network pharmacology revealed that 14 components, including senkyunolide A, glycycoumarin, licoflavonol, glycyrin, senkyunolide I, and senkyunolide H, form the key therapeutic basis of KQJF in targeting periodontitis. Significant targets and pathways were discerned as AKT1, MMP9, JUN, PTGS2, CASP3, TLR4, IL1ß, BCL2, PPARG, and pathways such as the TNF signaling pathway, NF-κB signaling pathway, osteoclast differentiation, and Wnt signaling pathway. Molecular docking demonstrated robust binding activity between these crucial targets and the key active ingredients. In vivo experimentation corroborated that, compared with the model group, KQJF significantly ameliorated symptoms and micro-CT imaging parameters of periodontitis in the rat model, down-regulating the expression of AKT1, MMP9, JUN, PTGS2, CASP3, TLR4, and IL1ß, while up-regulating the expression of BCL2 and PPARG. CONCLUSION: In summary, this study has pioneered a comprehensive exploration of the potential therapeutic constituents, targets, and mechanisms of KQJF for periodontitis treatment, adopting a synergistic strategy of "chemical component analysis-network pharmacology screening-in vivo animal experiment validation". This provides experimental evidence for the clinical application of KQJF and further in-depth research. Additionally, it presents an effective strategy for the research of other Chinese herbal formulations.

A Chinese herb preparation, honokiol, inhibits Streptococcus mutans biofilm formation.

OBJECTIVE: This study aimed to investigate the antibiofilm and anticariogenic effects of honokiol, a traditional Chinese medicine, on the cariogenic bacterium Streptococcus mutans (S. mutans). DESIGN: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of honokiol on S. mutans UA159 were measured. Then, S. mutans were treated with honokiol at concentrations of 1/2 MIC and 1/4 MIC. Extracellular polysaccharide (EPS) synthesis was assessed with confocal laser scanning microscopy (CLSM) and the anthrone-sulfuric method. Crystal violet staining and scanning electron microscopy (SEM) were used to demonstrate the characteristics and morphology of S. mutans biofilms. Colony-forming unit (CFU) assay was performed to observe the antibacterial effect of honokiol. Lactic acid production of 24-h biofilms was measured by the lactic acid assay. The expression level of caries-related genes (gtfB/C/D, comD/E and ldh) was identified by quantitative real-time PCR (qRTPCR) to explore the relevant mechanism. And the cytotoxic effect on human gingival fibroblasts (HGFs) was evaluated by the Cell Counting Kit-8 (CCK-8) assay. RESULTS: The MIC and MBC of honokiol on S. mutans were 30 µg/mL and 60 µg/mL, respectively. Honokiol inhibited biofilm formation, EPS synthesis and lactic acid production. It also decreased the expression of glucosyltransferases (Gtfs) and quorum sensing (QS) system encoding genes. Moreover, honokiol showed favorable biocompatibility with HGFs. CONCLUSIONS: Honokiol has an inhibitory effect on S. mutans and favorable biocompatibility, with application potential as a novel anticaries agent.

Preclinical evidence of probiotics in ulcerative colitis: a systematic review and network meta-analysis.

The imbalance of gastrointestinal microbial composition has been identified as the main factor of chronic inflammatory diseases. At present, probiotics have a beneficial effect on the microbial composition of the human gastrointestinal tract, but it is still controversial and the specific mechanism is unknown. The purpose of this network meta-analysis is to compare the mechanism of different probiotics on ulcerative colitis. PubMed, Embase, and Web of Science were searched till 16 November 2022. The SYRCLE risk bias assessment tool was used to assess the quality of the research studies. A total of 42 studies, 839 ulcerative colitis models, and 24 kinds of probiotics were finally included. The results showed that L. rhamnosus has the best effect in relieving weight loss and improving the Shannon index in the ulcerative colitis model. E. faecium has the best effect in reducing colon injury; L. reuteri has the best effect in reducing the DAI; L. acidophilus has the best effect in reducing the HIS index and increasing the expression of tight junction protein ZO-1; and L. coryniformis has the best effect in reducing the content of serum pro-inflammatory factor TNF-α. It indicated that probiotics can improve ulcerative colitis by improving histopathological manifestations, reducing inflammatory reaction, and repairing the mucosal barrier, and different probiotics showed different effects. However, considering the limitations of this study, preclinical studies that require more large samples and high-quality and more reliable and rigorous experimental designs and reports need to be conducted in the future. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/#record details, identifier CRD42022383383.

Efficacy and Safety of Traditional Chinese Medicine Based on the Method of "Nourishing Kidney and Clearing Heat" as Adjuvant in the Treatment of Diabetes Mellitus Patients with Periodontitis: A Systematic Review and Meta-Analysis.

Objective: The aim of this systematic review and meta-analysis was to assess the efficacy and safety of traditional Chinese medicine based on the method of "nourishing kidney and clearing heat" as an adjuvant in the treatment of diabetes mellitus patients with periodontitis. Methods: An electronic literature search was conducted in the China National Knowledge Infrastructure (CNKI), Wanfang Data, Chinese Scientific Journals Database (VIP), Chinese Biomedical Literature Database (CBM), PubMed, EMBASE, Web of Science, and Cochrane Library databases for articles published until October 2021. The primary outcomes were probing pocket depth (PPD), clinical attachment loss (CAL), plaque index (PLI), and sulcular bleeding index (SBI), while the secondary outcomes were tooth mobility (TM), glycosylated hemoglobin (HbA1c), fasting blood glucose (FBG), total effective rate, and adverse effects. Results: Eleven randomized controlled trials (RCT) were included in the meta-analysis. The pooled results showed PPD (WMD = 1.07, 95%CI: (0.82, 1.33), P < 0.00001, I 2 = 89%), CAL (WMD = 0.78, 95%CI: (0.62, 0.93), P < 0.00001, I 2 = 58%), PLI (WMD = 0.44, 95%CI: (0.09, 0.79), P=0.01, I2 = 97%), SBI (WMD = 0.87, 95%CI: (0.79, 0.95), P < 0.00001, I 2 = 37%), TM (WMD = 0.26, 95%CI: (0.21, 0.30), P < 0.00001, I 2 = 31%), HbA1c (WMD = 0.48, 95%CI: (0.28, 0.67), P < 0.00001, I2 = 26%), FBG (WMD = 1.34, 95%CI: (0.96, 1.72), P < 0.00001, I 2 = 52%), total effective rate (RR = 1.24, 95%CI: (1.14, 1.34), P < 0.00001, I 2 = 0%), and adverse effects (RR = 0.78, 95%CI: (0.20, 3.03), P=0.72, I 2 = 0%) in the traditional Chinese medicine based on the method of "nourishing kidney and clearing heat" + routine western medicine treatment (periodontal basic treatment, PBT, with or without antibiotic) group were significantly improved compared to control group, but no significant difference was observed for PLI at 2-3 months and 6 months. Conclusions: This review supports traditional Chinese medicine based on the method of "nourishing kidney and clearing heat" as an adjuvant to routine western medicine treatment in the management of diabetes mellitus patients with periodontitis. Within the limits of the evidence, the well-designed, long-term efficacy, and high-quality multicenter RCTs need to be further confirmed.

A Systematic Review and Meta-Analysis of Acupuncture Treatment for Oral Ulcer.

Background: Oral ulcer (OU) is a common oral mucosal disease manifested with obvious pain. In some studies, the efficacy of acupuncture in OU has been confirmed, but systematic reviews and meta-analyses for them are lacking. Our aim is to evaluate the efficacy of acupuncture in the treatment of OU. Methods: We searched the literature from eight databases from their inception to December 2021. We included randomized controlled trials of acupuncture for the treatment of oral ulcer. The meta-analysis was carried out using Review Manager 5.3 and Stata 16.0. The main outcomes were the effective rate and the recurrence rate, the secondary outcomes were the visual analogue score (VAS) and the ulcer healing time. Results: Totally, 18 studies were finally included in the meta-analysis, including 1,422 patients. In meta-analyses, we found that in comparison with Western medicine, acupuncture can improve effective rate (OR = 5.40, 95% CI: 3.40 to 8.58), reduce the ulcer recurrence rate (OR = 0.21, 95% CI: 0.13 to 0.33), and relieve the ulcer pain (MD = -2.26, 95% CI: -4.27to-0.24). In addition, compared with Western medicine, acupuncture plus Western medicine also can improve effective rate (OR = 2.95, 95% CI: 1.48 to 5.85). Compared with the Chinese medicine, the acupuncture plus Chinese medicine can improve the effective rate (OR = 8.26, 95% CI: 3.61 to 18.88) and relieve the ulcer pain (MD = -1.85, 95% CI: -2.51 to -1.19). Conclusion: Acupuncture may be more effective than Western medicine in terms of efficacy rate, and acupuncture combined with Western or Chinese medicine may have the potential to reduce the recurrence of ulcer and relieve the ulcer pain. However, due to limited evidence, higher quality and more rigorously designed clinical trials with larger sample sizes will be needed to further confirm our findings.

Implications of lysyl oxidase-like protein 3 expression in the periodontium of diabetic rats.

OBJECTIVES: Diabetes has been strongly associated with periodontal diseases. The periodontal ligament (PDL) has an abundant extracellular matrix (ECM). Lysyl oxidases (LOXs) are closely associated with various diseases caused by abnormal ECM functions, however, the role of LOXs in periodontal diseases induced by diabetes remains unclear. METHODOLOGY: In this study, 8-week-old Zucker diabetic fatty rats were used to establish a type 2 diabetes mellitus (T2DM) model. After 9 and 16 weeks, hematoxylin and eosin (H&E), Masson's trichrome, and immunohistochemical staining were performed. RESULTS: After 9 weeks, loose collagen fibers were found in the interradicular area of the diabetic group, in opposition to the control group. There were no significant differences in LOX expression between the diabetic and control groups (p>0.05). However, after 16 weeks, the diabetic group presented a disordered arrangement of the PDL, showing decreased collagen content and significantly increased lysyl oxidase-like protein 3 (LOXL3) expression when compared with the control group (p<0.05). This suggests that LOXL3 plays a significant role in periodontal histopathological changes in diabetic rats. CONCLUSION: Our study showed elevated LOXL3 expression in the PDL of diabetic rats after 16 weeks, suggesting that LOXL3 may be involved in the occurrence and development of periodontal histopathological changes in diabetic rats. LOXL3 could be further used as an indicator for the early diagnosis of diabetic periodontitis in T2DM patients in clinical settings.

Association between Helicobacter pylori infection and the risk of colorectal cancer: A systematic review and meta-analysis.

BACKGROUND: The existing evidence on the relationship between Helicobacter pylori infection and the risk of colorectal cancer is inconsistent. We conducted a systematic review with a meta-analysis to explore this relationship and to determine whether the relationship varies according to the study characteristics. METHODS: We searched the PubMed, OVID, EMBASE database, and the reference lists of pertinent articles published up to October 2019 by 2 researchers independently. Summary odds ratios (OR) with their 95% confidence intervals (CIs) were estimated using a random-effects model. RESULTS: Forty seven studies including 17,416 cases of colorectal cancer (CRC) and 55,811 cases of control were included. Overall, H. pylori infection was associated with an increased risk of CRC (OR = 1.70 95% CI 1.64-1.76, I = 97%), although there was significant heterogeneity among the studies. Subgroup analysis revealed that the positive correlation might vary by the design of study conducted. CONCLUSION: This meta-analysis demonstrates a positive association between H. pylori infection and the risk of colorectal cancer.

A systematic review and meta-analysis of acupuncture treatment for oral ulcer.

BACKGROUND: Oral ulcers (OU) is a common oral mucosal disease manifested with obvious pain; in some studies, the efficacy of acupuncture in OU has been confirmed, but the systematic reviews and meta-analyses for them are lacking. Our aim is to evaluate the efficacy and safety of acupuncture in the treatment of OU. METHODS: Relevant randomized controlled trials (RCTs), quasi RCTs and non-RCTs will be identified by systematic searching from the following electronic databases: PubMed, Embase, the Cochrane Library, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, China Science and Technology Journal database, and Wanfang Data (since inception of the databases to present). In addition, ongoing trials will be retrieved from the Chinese Clinical Trial Register, World Health Organization International Clinical Trials Registry Platform, Clinical Trials, and The Clinical Trials Register. Grey literature will be also taken into consideration, including academic dissertation, minutes of the meeting from Chinese Biomedical Literature Database, China National Knowledge Infrastructure, China Science and Technology Journal database, and Wanfang Data. There are no language restrictions. RESULTS: Ethical approval is not required because this study is based on published papers. After peer-review, the study will be disseminated in scientific journals and conferences. CONCLUSION: This systematic review will provide evidence for the efficacy and safety of acupuncture for Oral ulcers. TRIAL REGISTRATION NUMBER: CRD42020144911.

Risk of hepatitis B virus transmission via dental handpieces and evaluation of an anti-suction device for prevention of transmission.

We evaluated the risk of hepatitis B virus (HBV) transmission via dental handpieces and the effects of an anti-suction device in preventing HBV contamination. The results of our study show that under certain conditions, HBV transmission can occur when an anti-suction device is used during dental procedures. We conclude that such devices may decrease contamination, but do not eliminate it.

Effects of Nidus Vespae extract and chemical fractions on glucosyltransferases, adherence and biofilm formation of Streptococcus mutans.

Nidus Vespae (the honeycomb of Polistes olivaceous, P. japonicus Saussure and Parapolybiavaria fabricius) have been extensively used in traditional Chinese medicine, given their multiple pharmacological activities, including antimicrobial, anti-inflammatory, anti-virus, anti-tumor and anesthetic properties. The present study evaluated the anti-glucosyltransferases (GTFs) activity, anti-adherence and anti-biofilm properties of 95% ethanol/water extract, cyclohexane/ethyl acetate, petroleum ether/ethyl acetate and chloroform/methanol fractions of Nidus Vespae. Chloroform/methanol fraction showed a remarkable capacity for inhibiting the adherence of Streptococcus mutans ATCC 25175 to saliva-coated hydroxyapatite disc (S-HA) at sub-MC concentrations. In addition, the Nidus Vespae extract and chemical fractions significantly inhibited the activity of cell-associated and extracellular GTFs at sub-MIC concentrations, and the chloroform/methanol fraction was the most effective one. For the anti-biofilm activity assays, minimum biofilm inhibition concentrations (MBIC50) and minimum biofilm reduction concentrations (MBRC50) were determined using the microdilution method. The chloroform/methanol fraction showed the highest anti-biofilm activities with a MBIC50 of 8mg/ml and a MBRC(50) of 16mg/ml against Streptococcus mutans ATCC 25175. The significant inhibition of GTFs activity and biofilm formation demonstrated by Nidus Vespae shows it to be a promising natural product for the prevention of dental caries.

Implications of lysyl oxidase-like protein 3 expression in the periodontium of diabetic rats

Abstract Objectives Diabetes has been strongly associated with periodontal diseases. The periodontal ligament (PDL) has an abundant extracellular matrix (ECM). Lysyl oxidases (LOXs) are closely associated with various diseases caused by abnormal ECM functions, however, the role of LOXs in periodontal diseases induced by diabetes remains unclear. Methodology In this study, 8-week-old Zucker diabetic fatty rats were used to establish a type 2 diabetes mellitus (T2DM) model. After 9 and 16 weeks, hematoxylin and eosin (H&E), Masson's trichrome, and immunohistochemical staining were performed. Results After 9 weeks, loose collagen fibers were found in the interradicular area of the diabetic group, in opposition to the control group. There were no significant differences in LOX expression between the diabetic and control groups (p>0.05). However, after 16 weeks, the diabetic group presented a disordered arrangement of the PDL, showing decreased collagen content and significantly increased lysyl oxidase-like protein 3 (LOXL3) expression when compared with the control group (p<0.05). This suggests that LOXL3 plays a significant role in periodontal histopathological changes in diabetic rats. Conclusion Our study showed elevated LOXL3 expression in the PDL of diabetic rats after 16 weeks, suggesting that LOXL3 may be involved in the occurrence and development of periodontal histopathological changes in diabetic rats. LOXL3 could be further used as an indicator for the early diagnosis of diabetic periodontitis in T2DM patients in clinical settings.

Efficiency and productivity measurement of rural township hospitals in China: a bootstrapping data envelopment analysis.

OBJECTIVE: Township hospitals (THs) are important components of the three-tier rural healthcare system of China. However, the efficiency and productivity of THs have been questioned since the healthcare reform was implemented in 2009. The objective of this study is to analyse the efficiency and productivity changes in THs before and after the reform process. SETTING AND PARTICIPANTS: A total of 48 sample THs were selected from the Xiaogan Prefecture in Hubei Province from 2008 to 2014. OUTCOME MEASURES: First, bootstrapping data envelopment analysis (DEA) was performed to estimate the technical efficiency (TE), pure technical efficiency (PTE) and scale efficiency (SE) of the sample THs during the period. Second, the bootstrapping Malmquist productivity index was used to calculate the productivity changes over time. RESULTS: The average TE, PTE and SE of the sample THs over the 7-year period were 0.5147, 0.6373 and 0.7080, respectively. The average TE and PTE increased from 2008 to 2012 but declined considerably after 2012. In general, the sample THs experienced a negative shift in productivity from 2008 to 2014. The negative change was 2.14%, which was attributed to a 23.89% decrease in technological changes (TC). The sample THs experienced a positive productivity shift from 2008 to 2012 but experienced deterioration from 2012 to 2014. CONCLUSIONS: There was considerable space for TE improvement in the sample THs since the average TE was relatively low. From 2008 to 2014, the sample THs experienced a decrease in productivity, and the adverse alteration in TC should be emphasised. In the context of healthcare reform, the factors that influence TE and productivity of THs are complex. Results suggest that numerous quantitative and qualitative studies are necessary to explore the reasons for the changes in TE and productivity.

[An in vitro study on effect of Nidus vespae extract on the acid production of three strains of oral bacteria].

OBJECTIVE: To inquire into the effect of different of Nidus Vespae extract (NVE) on growth and acid production of Streptococcus mutans, Streptococcus sanguis and Actinomyces viscosus. METHODS: Streptococcus mutans ATCC 25175, Streptococcus sanguis ATCC 10556 and Actinomyces viscosus ATCC 19246 were chosen as the experimental bacteria. Four extracts of Nidus Vespae were prepared and then the effects of these Nidus Vespae extracts on the acid production were determined. RESULTS: All of Nidus Vespae extracts could inhibit the growth the of the three strains, and NVE1, NVE3, NVE4 could inhibit the acid production of the three strains, NVE2 could inhibit the acid production of Actinomyces viscosus. CONCLUSION: Four extracts of Nidus Vespae could inhibit the acid production of three bacteria strains.

The TF-miRNA Coregulation Network in Oral Lichen Planus.

Oral lichen planus (OLP) is a chronic inflammatory disease that affects oral mucosa, some of which may finally develop into oral squamous cell carcinoma. Therefore, pinpointing the molecular mechanisms underlying the pathogenesis of OLP is important to develop efficient treatments for OLP. Recently, the accumulation of the large amount of omics data, especially transcriptome data, provides opportunities to investigate OLPs from a systematic perspective. In this paper, assuming that the OLP associated genes have functional relationships, we present a new approach to identify OLP related gene modules from gene regulatory networks. In particular, we find that the gene modules regulated by both transcription factors (TFs) and microRNAs (miRNAs) play important roles in the pathogenesis of OLP and many genes in the modules have been reported to be related to OLP in the literature.

[Dental caries conditions of 3,439 disabled Yi and Han individuals in Liangshan Yi Autonomous Prefecture in Sichuan province, China].

OBJECTIVE: This study aims to conduct a survey of the oral health status of disabled individuals in Liangshan Autonomous Prefecture in Sichuan province. This study was also conducted to prepare caries prevention planning in the region. METHODS: On the basis of the Oral Health Surveys: Basic Methods of WHO and the Third National Oral Health Epidemiological Sample Survey Scheme, we investigated caries infecting disabled individuals who live in one big city (Xichang city), three counties (Bhutto county, Muli Tibetan autonomous county, and Huili county), and 46 towns and villages of Liangshan Autonomous Prefecture in Sichuan province, by multi-stage stratified and cluster sampling. RESULTS: Among 3,439 disabled individuals, 2,085 were males and 1,354 were females; among these individuals, 815 live in the city and 2,624 live in rural areas. Furthermore, 2,177 were Han natives and 1,262 were Yi natives (ethnic). The caries prevalence rate and mean DMFT of disabled individuals in Liangshan Autonomous Prefecture in Sichuan province were 87.1% and 9.53, respectively. In Yi, the caries prevalence rate and mean DMFT of disabled individuals in Liangshan Autonomous Prefecture in Sichuan province were 85.8% and 9.93, respectively; in Han, the caries prevalence rate and mean DMFT of disabled individuals in Liangshan Autonomous Prefecture in Sichuan province were 87.9% and 9.29, respectively. No significant difference was found in the two groups of native (P > 0.05). A very low filling rate of 0.2% was also recorded. CONCLUSION: Disabled individuals from Liangshan Autonomous Prefecture in Sichuan province exhibited a high prevalence of caries in permanent teeth. The oral health status of this special group of disabled individuals should be provided intensive care.

[Comparison of preventive effects of two kinds of dental handpieces on viral contamination at different rotating times].

OBJECTIVE: It has been demonstrated that when a high-speed handpiece stops rotating, negative pressure will form. Thus, contaminating fluid in which there are many kinds of bacteria and viruses from the external environment will retract into various compartments of the handpiece and the dental unit. The purpose of the study is to compare the preventing effect of antisuction designed handpiece and conventional handpiece on viral contamination at different rotating times. METHODS: Twenty handpieces with or without antisuction device (10 of each) were used in the study. Each handpiece was submerged into 10(-6) microg/microl HBV particle solution rotating 5 and 10 times respectively (every time rotating for 10 seconds). Samples were obtained from the water line and chip air line of the handpieces and examined by RT-PCR. RESULTS: At the same rotating times, there was statistical significance of the viral concentration between the two kinds of handpieces (P < 0.05) . However, there was no statistical significance of the viral concentration between different rotating times in each group (P > 0.05). CONCLUSION: Contamination taking place in both water and air lines of dental handpiece was not enhanced by increasing the number of rotating times of the handpiece. The antisuction devices installed into the water line and chip air line were demonstrated to prevent viral contamination effectively.