Promotion of Dental Pulp Cell Migration and Pulp Repair by a Bioceramic Putty Involving FGFR-mediated Signaling Pathways

Mineral trioxide aggregate is the currently recommended material of choice for clinical pulp repair despite several disadvantages, including handling inconvenience. Little is known about the signaling mechanisms involved in bioceramic-mediated dental pulp repair-particularly, dental pulp cell (DPC) migration. This study evaluated the effects of iRoot BP Plus, a novel ready-to-use nanoparticulate bioceramic putty, on DPC migration in vitro and pulp repair in vivo, focusing on possible involvement of fibroblast growth factor receptor (FGFR)-related signaling, including mitogen-activated protein kinase and Akt pathways. Treatment with iRoot BP Plus extracts enhanced horizontal and vertical migration of DPCs, which was comparable with the effects induced by mineral trioxide aggregate extracts. The DPCs exposed to iRoot BP Plus extracts demonstrated no evident apoptosis. Importantly, treatment with iRoot BP Plus extracts resulted in rapid activation of FGFR, p38 mitogen-activated protein kinase, extracellular signal-regulated kinase (ERK) 1/2, c-Jun-N-terminal kinase (JNK), and Akt signaling in DPCs. Confocal immunofluorescence staining revealed that iRoot BP Plus stimulated focal adhesion formation and stress fiber assembly in DPCs, in addition to upregulating the expression of focal adhesion molecules, including p-focal adhesion kinase, p-paxillin, and vinculin. Moreover, activation of FGFR, ERK, JNK, and Akt were found to mediate the upregulated expression of focal adhesion molecules, stress fiber assembly, and enhanced DPC migration induced by iRoot BP Plus. Consistent with the in vitro results, we observed induction of homogeneous dentin bridge formation and expression of p-focal adhesion kinase, p-FGFR, p-ERK 1/2, p-JNK, and p-Akt near injury sites by iRoot BP Plus in an in vivo pulp repair model. These data demonstrate that iRoot BP Plus can promote DPC migration and pulp repair involving the FGFR-mediated ERK 1/2, JNK, and Akt pathways. These findings provide valuable insights into the signaling mechanisms underlying nanoparticulate bioceramic-mediated pulp repair.

Autoantibodies response to MDM2 and p53 in the immunodiagnosis of esophageal squamous cell carcinoma

The human homologue of the mouse double minute 2 (MDM2) is known to be overexpressed in a variety of human malignancies. As one of E3 ubiquitin-protein ligases, MDM2 interacts with the tumour suppressor p53 by mediating ubiquitination and degradation of p53. Since abnormally expressed proteins can induce autoimmune response, to further examine whether sera from patients with esophageal squamous cell carcinoma (ESCC) exhibited immunoreactivity against MDM2 and p53, autoantibody responses to MDM2 and p53 were evaluated by enzyme-linked immunosorbent assay (ELISA) in sera from patients with ESCC and normal individuals. Positive results were also confirmed by Western blotting and indirect immunofluorescence assay. The results demonstrated that the positive rate of autoantibody against p53 and MDM2 in ESCC sera was 22.9% (36/157) and 14.0% (22/157), whereas this rate was 0% (0/85) and 1.2% (1/85), respectively, in normal individuals. Some of the sera with antibodies specific for MDM2 also contained antibodies against p53. And there was an increase of positive antibody reactions reaching a frequency of 35% (55/157) combination with MDM2 and p53. This was significantly higher than the frequency of antibodies in normal individuals (P < 0.01). Our preliminary results suggest that autoantibodies against MDM2 and p53 may be useful serum biomarkers in the immunodiagnosis of ESCC.

[miR-200b suppresses glioma cell invasion by targeting PROM1]

OBJECTIVE

To explore whether miR-200b suppresses tumor cell invasion by targeting PROM1, thus to reveal the molecular mechanism that miR-200b functions as a tumor suppressor in glioma.

METHODS

PROM1 3'UTR-luciferase vector was constructed and dual-luciferase reporter gene assay was employed to examine the effect of miR-200b on luciferase activity. Human glioblastoma U87 cells were transfected with miR-200b mimics, and next qRT-PCR and Western blotting were performed to detect the expressions of PROM1 mRNA and protein. The effect of PROM1 down-regulation on invasion was observed after PROM1 siRNA were transfected into U87 cells.

RESULTS

The miR-200b bound to the 3'-untranslated region (UTR) of PROM1 and inhibited the luciferase activity. Its luciferase activity was down-regulated by 57.0% (P < 0.01). PROM1 protein and mRNA expressions were significantly down-regulated when miR-200b was overexpressed in the U87 cells (P < 0.05). siRNA-mediated down-regulation of PROM1 suppressed the potential of cell invasion. The invasion ability of SKOV3 cells after transfection with siRNA-PROM1 was significantly lower than that in the negative control cells (P < 0.05).

CONCLUSION

miR-200b may suppress cell invasion by targeting PROM1 in glioma.

Review on nanomaterials synthesized by vapor transport method: growth and their related applications

Nanostructures with different dimensions, including bulk crystals, thin films, nanowires, nanobelts and nanorods, have received considerable attention due to their novel functionalities and outstanding applications in various areas.

Effect of BioAggregate on osteoclast differentiation and inflammatory bone resorption in vivo

AIM

To investigate the effect of BioAggregate (Innovative Bioceramix, Vancouver, BC, Canada) on lipopolysaccharide (LPS)-induced bone destruction in vivo and to compare its performance with that of mineral trioxide aggregate (MTA; Dentsply Tulsa Dental, Tulsa, OK, USA).

METHODOLOGY

Mouse bone marrow macrophages (BMMs) were primary cultured and treated with several concentrations of BioAggregate and MTA extracts. Cell viability was measured with a Cell Counting Kit-8 assay, whilst in vitro osteoclast differentiation was evaluated with tartrate-resistant acid phosphatase (TRAP) staining. LPS-induced mouse calvarial bone destruction model was established to assess the effect of BioAggregate and MTA extracts in vivo. Mice were killed on day 7, and calvarial bones were prepared for microcomputed tomography scanning, histologic analysis and double-immunofluorescence staining. Statistical tests used were one-way anova followed by Student-Newman-Keuls test.

RESULTS

BioAggregate extracts displayed no obvious cytotoxicity to BMMs and significantly inhibited (P < 0.01) the differentiation of RANKL-stimulated BMMs. Comparable effects were induced by MTA. BioAggregate and MTA extracts markedly reduced (P < 0.01) osteoclast numbers and attenuated (P < 0.05) bone resorption in LPS-challenged mouse calvaria. The expression levels of osteoclastogenic cathepsin K and its upstream regulator nuclear factor of activated T-cell cytoplasmic 1 and c-Fos were also decreased by BioAggregate and MTA extracts.

CONCLUSIONS

BioAggregate and MTA showed comparable inhibitory effect on osteoclast differentiation and inflammatory bone resorption in vivo.

Thulium laser resection for bladder neck obstruction in women

AIM

The aim of this paper was to investigate the efficacy of thulium laser resection of bladder neck in women with bladder neck obstruction (BNO).

METHODS

Clinical information of 86 women with BNO who were treated in our hospital from Jan 2011 to Dec 2012 was retrospectively reviewed; 46 patients received thulium laser resection (group 1), and the remaining patients were treated with standard electric resection (group 2). Maximum urinary flow rate (MFR), residual urine volume (RV), overactive bladder symptom score (OABSS) and quality of life (QOL) were determined before and after surgery. These patients were followed up at 1 week, 3 months, and 12 months after surgery.

RESULTS

The RV levels after surgery in groups 1 were significantly lower than those before operation. MFR significantly increased after surgery when compared with preoperation, OABSS and QOL score markedly decreased at 3 months after surgery (P<0.05). Thulium laser resection had advantages in postoperative catheter retaining time (2.18±0.73 d vs. 4.24±1.01 d), postoperative hospitalization time (3.25±0.61 d vs. 4.73±1.41 d), Intraoperative blood loss (11.5±1.53 mL vs. 32.32±8.53 mL) and total cost ($1415±71 vs. $1148±59) over standard electric resection (P<0.05), but the operative time was comparable between two groups (18.36±5.45 min vs. 19.25±7.08 min) (P >0.05). In group 2, urethral stricture was seen in 1 patient, and two patients suffered from temporary incontinence, being back to normal in one month. However, urethral stricture and incontinence were not observed in group 1.

CONCLUSION

Thulium laser resection is a simple, safe and effective strategy for the treatment of bladder neck obstruction in women.

Kinetics of glycogen synthase kinase (GSK)3β and phosphorylated GSK3β (Ser 9) expression in experimentally induced periapical lesions

AIM

To investigate the kinetics of GSK3β and p-GSK3β (Ser 9) expression in experimentally induced rat periapical lesions and to explore their possible functions in the pathogenesis of periapical lesions.

METHODOLOGY

Periapical lesions were established in Wistar rats by occlusal pulp exposure in mandibular first molar teeth. The animals were killed on days 0, 7, 14, 21 and 28. Micro-computed tomographic, histological and enzyme histochemical analyses were performed to detect the progression of periapical lesions. Immunohistochemistry, double-dye immunofluorescence and Western blot were performed to determine the expression of GSK3β and p-GSK3β (Ser 9) in periapical tissues.

RESULTS

From day 0 to day 28, the lesion volume and area gradually expanded, and the GSK3β-positive cells gradually ascended. A few p-GSK3β (Ser 9)-positive cells and osteoclasts appeared on day 7 and then climaxed on day 14. The numbers then simultaneously decreased from day 21 to day 28. Western blot analysis revealed that p-GSK3β (Ser 9) and GSK3β proteins were expressed at all time-points. The positive cells and protein expression ratio of p-GSK3β (Ser 9) against GSK3β increased from day 0 to day 14 and then decreased from day 14 to day 28. Finally, double-dye immunofluorescence assay revealed that p-GSK3β (Ser 9)-positive and RANKL-positive cells were co-localized around periapical lesions on days 14 and 28.

CONCLUSIONS

GSK3β and p-GSK3β (Ser 9) can be observed and may be involved in alveolar bone resorption and inflammatory response in periapical lesions, as well as associated with periapical lesion pathogenesis.

Transcriptome profiling of prostate tumor and matched normal samples by RNA-Seq

BACKGROUND

RNA-Sequencing (RNA-Seq) has greatly influenced cancer researches, and it provides an unprecedented resolution in estimating gene expression and has less signal noises compared to cDNA microarray.

AIM

We aimed to identify a list of protein-coding genes and lincRNAs that are expressed differentially between tumor and normal tissues.

MATERIALS AND METHODS

In this study, we analyzed including 10 human prostate tumor tissues and their matched normal tissues transcriptome dataset generated by recently developed RNA-Seq technology.

RESULTS

By aligning short reads to human RefSeq genes and lincRNAs, we identified 10 RefSeq genes that were differentially expressed between tumor and normal samples with a p-value < 0.05, which were sufficiently enough to distinguish these two groups. Further loosing the p-value cutoff to 0.1 identified an lincRNA which is antisense to Cullin-associated and neddulation-dissociated 1 (CAND1), whose expression is repressed in prostate tumor cells. By examining the expression of CAND1 and its antisense lincRNA in the transcriptome dataset, we found an interaction between them as high expression of CAND1 and low expression of lincRNA is normal samples, and verse visa in tumor samples.

CONCLUSIONS

These findings suggest the important usage of RNA-Seq in cancer studies for biomarker development and functional investigation.

NOD1 expression elicited by iE-DAP in first trimester human trophoblast cells and its potential role in infection-associated inflammation

OBJECTIVES

The underlying mechanisms of protective immunity of placental trophoblast cells against bacterial infection remain largely unknown. NOD1 are intracellular pattern recognition receptors that are activated by bacterial peptides and mediate innate immunity. This study aimed to investigate the expression and function of NOD1 in first trimester trophoblast cells, and evaluate the potential role of trophoblast cells in infection-associated inflammation.

STUDY DESIGN

Human extravillous trophoblast cell line HTR8 cells were stimulated with various concentrations of iE-DAP for various periods of time. NOD1 expression was detected by immunofluorescence, and the changes in NOD1 and RICK mRNA and protein in H8 cells were determined by real-time polymerase chain reaction and Western blot analysis. The concentrations of interleukin (IL)-8 and IL-6 secreted by H8 cells were examined by enzyme-linked immunosorbent assay. NF-κB transcription activity and P65 expression were detected by electrophoretic mobility shift assay and Western blot analysis.

RESULTS

H8 cells expressed NOD1, and the effects of iE-DAP on NOD1 were dose- and time-dependent. The concentration of IL-8 increased gradually with increasing concentration of iE-DAP, and the levels of IL-8 and IL-6 were associated with the duration of exposure to iE-DAP. The dose of iE-DAP was significantly associated with expression of RICK and P65, and stimulation of H8 cells by iE-DAP altered NF-κB transcription activity.

CONCLUSIONS

NOD1 may have a role in mediating infection-associated inflammation. Once iE-DAP is recognized by NOD1, the inflammatory response may be induced via NOD1-RICK-NF-κB-mediated pathways.

Expression of a cytokine, interleukin-23, in experimental periapical lesions

AIM

To investigate the expression of interleukin (IL)-23, a new member of the IL-12 family, in experimental periapical lesions.

METHODOLOGY

Periapical lesions were induced in Wistar rats by occlusal surface pulp exposure in mandibular first molars. The rats were randomly sacrificed 0, 7, 14, 21, 28, 35, 42 and 56 days after pulp exposure. The jaws that contained the first molars were obtained and routinely prepared for radiographic, histological, enzyme histochemical, immunohistochemical and double immunofluorescence analyses. Data were analysed by one-way analysis of variance and the Pearson correlation test.

RESULTS

The number of IL-23-positive cells increased from day 7 to day 35 and then gradually decreased. The number of osteoclasts increased and peaked on day 14 and then gradually decreased from day 21 to day 56. A significant positive correlation existed between the number of IL-23 positive cells and the size of bone resorption in periapical lesions from day 7 to day 56 (r = 0.875, P < 0.01).

CONCLUSIONS

Interleukin-23 can be observed and may be associated with inflammatory response and bone resorption in periapical lesions.

Comparison of spermatogenic damage induced at 6 months after ligation of the vas deferens at proximal and distal locations in the rabbit

Recent study in rabbits demonstrated that vasectomy via the inguinal canal did not result in any spermatogenic damage 3 months postoperation; this study aimed to determine whether the damage would occur in a longer term. The left or right vas deferens was ligated near the epididymal head (unilateral proximal vasectomy, 12 animals) or via the inguinal canal (unilateral distal vasectomy, 11 animals) in adult male rabbits, with a sham operation being performed on the contralateral side. Six months postoperation, testes, epididymides and vasa deferentia were removed and methacrylate resin-embedded sections prepared to evaluate spermatogenesis by histological (qualitative) and stereological (quantitative) studies. The juxta-epididymal segment of the occluded vas deferens was severely distended (filled with sperm) in 10 of the 11 animals with distal vasectomy and moderately or slightly distended in nine of the 12 animals with proximal vasectomy. Severe spermatogenic damage occurred in seven animals with proximal vasectomy (the juxta-epididymal vas moderately or slightly distended), in only one animal with distal vasectomy (the vas not severely distended). In conclusion, spermatogenic damage occurred at 6 months postvasectomy in some animals, especially those with proximal vasectomy and therefore shorter occluded reproductive tract for sperm storage; the damage was probably intra-tract pressure mediated.

The prevalence of and risk factors for non-carious cervical lesions in adults in Hubei Province, China

OBJECTIVES

To describe the prevalence of non-carious cervical lesions (NCCLs) and to assess the relative affects of risk factors on NCCLs in middle-aged and elderly people in Hubei Province, China.

DESIGN

A sample of 2,160 adults, aged 35-44 years and 65-74 years and balanced by age, gender, and urbanization, participated in the cross sectional epidemiological survey. Non-carious cervical lesions were examined using a modified Tooth Wear Index. Data were collected based on structured questionnaires that assessed general information as well as oral health.

RESULTS

The prevalence of non-carious cervical lesions was 38.8% for 35-44-year-olds and 56.6% for 65-74-year-olds. The first premolars, canines, and second premolars showed the highest prevalence of lesions, while the second molars demonstrated the least. Several risk factors such as age (OR = 2.45, p < 0.001), location (OR = 1.68, p = 0.001), frequency of toothbrushing (OR = 1.33, p = 0.016), bruxism (OR = 1.37, p < 0.001), and family income (OR = 1.44, p < 0.001) were found to be associated with lesion occurrence.

CONCLUSIONS

The prevalence of non-carious cervical lesions was relatively high in the middle-aged and elderly persons in China and was also associated with socio-behavioural risk factors.